Polymorphism: Empowering your objects

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Hi there readers, So, we’re finally getting into the final pilar of object oriented programming, polymorphism. It’s a strange word at first, but we get use to it pretty fast.

What does the word polymorphism mean?

The root of polymorphism is traced back to the greeks. Poly means many and morphism mean forms. Basically, polymorphism gives an object the ability of having multiple forms. The fact that an object can have multiple forms means that while using inheritance of dependency injection (an advance topic which will be mentioned later), we don’t have to care what kind of object we’re calling during runtime. Having multiple forms means that while calling a certain function, in the hierarchy of objects, custom or not, it won’t matter which objects is being called. A real world example of polymorphism

Example

Everyone is a person, but each one as his own waking up routine at a specific time of the day:

  • As a waiter
  • As a lawyer
  • As a student taking classes at nights

Method overriding? Virtual methods? What are those ??

Basically, virtual methods are found in the parent class. Virtual methods are behaviors in parent objects which can be overridden by their children. To make sure a method can be use by the children and be overridden, not only it must have the virtual keyword in its signature, but it should also have the protected keyword to make sure that only children can use it. This is a key concept in oriented object programming.

Easily, it’s possible to see why such a feature can be attractive for programmers. We love code reuse and we hate rewriting the same piece of code. Some readers might wonder why we hate rewriting code, right ? Well, it’s pretty simple in fact. It’s a bad programming behavior, YOU SHOULD NOT DO THAT ! Having to rewrite code will double or even triple or X factor time the amount of time you need to invest into maintaining the software.

Back to virtual methods. Having a basic foundation for most of the component in your system simplifies the work that must be completed. More than just this, when you’re overriding behaviors, it’s because you have a darn god reason to do this. in fact, while you’re testing your code or going over your software a few months after writing it, you’ll understand exactly why you did why you did. We usually do this because we have a good reason why.

public abstract class Human
{
   protected virtual void Greetings(string name)
   {
       Console.WriteLine("Hi, my name is {0}:", name);
   }
}

public class Doctor : Human
{
   public void GreetingPatient(string patientName,string doctorName)
   {
     Console.WriteLine("Hello {0}",patientName);
     Greetins(doctorName);
   }
   protected override void Greetings(string name)
   {
     Console.WriteLine("Hi, I'm doctor {0}. It's nice to meet you.",name);
   }
 }
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Inheritance: More than just titles or money

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Hi there readers,

We have talked about the first principle of object oriented programming in an earlier post. Now, it would be time to talk about the second one, inheritance. In the normal world, we talk about inheritance when one is about to receive some piece of land or a title from a loved one in his/her family. In the programming realm, it is more than this. In OOP, inheritance happens when a class is based on another class . This relation is special because they share the same implementation. Doing so, the class (B), who inherits from the other (A), share the same behavior that A has. But why would programmers act like this? Why not simply copy-paste the code from the class A to the class B? Those are actually good questions you might have had.

I don’t know if you remember from earlier posts, but I had mentioned that having a software which had a lot of code was not the goal you should think of while writing code. Sometimes, there won’t be any other way than having a software which has 10,000.0 lines of code and it is okay. But what we aimed for is having a software that is as maintainable as it can be. When I say maintainable, what I mean is that simply finishing a project won’t mean that it won’t change in one day or one month or five years. A query from a client can make your project change over time,and while you’re going through those changes, you don’t want to change all the code that was written before. Having maintainable code can be achieved through different methods, and by this I don’t mean the methods we usually write in order to complete operations. One of them is code reuse.

Like it was said earlier, class B inherits from class A. Inheritance is a mechanism for code reuse. Not only B gets all the same behavior that A has,  but B has accessed to all the attributes from the class A. Has much as inheritance is a good principle to follow while doing OOP, there is something that we must keep in mind while using inheritance. When a class inherits from another, what we’re trying to achieve is to specialize a concept by adding new behaviors to the class. Basically, we have what we call the superclass which has some states and behaviors that can be common for many situations. Then, we have the subclasses which inherits those traits but add new ones. For example, we could have the superclass Person which has a Weight, Name and Age. Now, we have the classes Student, Manager and Employee.

The Student objects, since inheriting from Person, already have Name,Weight and Age. But a student has more than simply that like a grade point average (GPA) or a student id (ID). Employee is also inheriting from Person but has the properties Salary and  Bonus. Finally, we have Manager which inherits from Employee but only overrides behaviors from Employee.

That’s a benefit from inheritance. Even though we inherits from a superclass, if we like the behaviors from the previous class but there is some things that need to be change, then we can override those behaviors in order to achieve what we truly wish to do. Down below, we’ll see in code exactly what I said we can do with inheritance.


using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication1
{
    class Program
    {
      static void Main(string[] args)
      {
         Person aPerson = new Person("Bob", 70.45, 23);// creating a person
         aPerson.SayingHello("Sarah");

         Student aStudent = new Student("Bobby", 1023453235, 3.98, 83.67, 22); //creating a student
         aStudent.PrintStudentAverage(); //Printing the student's average

        Employee anEmployee = new Employee("Tom", 5, 25.50, 23); //creating an employee
        anEmployee.SayingHello(aStudent.Name); //The employee says hi to the student
        anEmployee.PrintEmployeeSalary(); // Printing the salary of the employee

        Manager aManager = new Manager("Kevin", 43.45, 23, 4);
        aManager.SayingHello(anEmployee.Name);
        aManager.PrintEmployeeSalary();

        Console.ReadLine();//Press Enter to quit this application
     }
   }

   public class Person
   {
     private double _weight; //we define the fields by starting with the underscore (_)

     public double Weight
     {
        get { return _weight; }
       set { _weight = value; } //We'll let the weight like this because over time, it can change
     }

     private String _name;

     public String Name
     {
        get { return _name; }
        set { _name = value; }
        //Usually, the name of a person does not change, so we'll make it private.
       //This means that no one who can access an object of Person will be able to modify the name
     }

     private int _age;

     public int Age
     {
       get { return _age; }
       set { _age = value; }
     }
     //Constructor
     public Person(String aName,double aWeight, int anAge)
     {
       Name = aName;
       Weight = aWeight;
       Age = anAge;
     }

     public Person() { }

     public void SayingHello(String personName)
     {
        Console.WriteLine("Hi, my name his : {0}. It his a pleasure to make your acquantaince {1} !", Name, personName);
     }
  }

     public class Student : Person
     {
        private int _studentID;

       public int StudentID
       {
          get { return _studentID; }
          set { _studentID = value; }
       }

       private double _gpa;

       public double GPA
       {
          get { return _gpa; }
          set { _gpa = value; }
       }

       private int _numberOfClasses;

       public int NumberClassesForTheSemester
       {
          get { return _numberOfClasses; }
          set { _numberOfClasses = value; }
       }

       private int _numberOfCredits;

       public int NumberOfCredits
       {
         get { return _numberOfCredits; }
         set { _numberOfCredits = value; }
       }

        public Student(String name, int id, double gpa,double weight, int anAge)
        {
           this.Name = name;
           this.StudentID = id;
           this.GPA = gpa;
           this.Weight = weight;
           this.Age = anAge;
        }

        public void PrintStudentAverage()
        {
            Console.WriteLine("The average of {0} is {1}", this.Name, GPA);
        }

        private void ComputeStudentGPA()
        {
           //not how we actually do it, it is more as a behaviour to add to this class
           GPA = NumberClassesForTheSemester / NumberOfCredits;
        }
     }

    public class Employee : Person
    {
      private double _hourlyWage;

      public double Salary
      {
         get { return _hourlyWage; }
         set { _hourlyWage = value; }
      }

       private int _bonus;

       public int EndOfyearBonus
       {
          get { return _bonus; }
          set { _bonus = value; }
       }

       private int _yearInCompany;

       public int YearsInCompany
       {
          get { return _yearInCompany; }
          set { _yearInCompany = value; }
       }

       public Employee(String name, int yearsOfLoyalty,double salary, int age)
       {
          this.Name = name;
          this.YearsInCompany = yearsOfLoyalty;
          this.Salary = salary;
          this.Age = age;
       }

        public Employee() { }

        public virtual void ReceiveBonus(int bonus)
        {
            EndOfyearBonus = YearsInCompany * 2 * bonus;
        }

        public void PrintEmployeeSalary()
        {
           Console.WriteLine("This is the salary : {0} $/h of {1}", this.Salary, this.Name);
        }
     }
     public class Manager : Employee
     {
        public Manager(String name, double salary, int age, int numberOfYears)
        {
           this.Name = name;
           this.Salary = salary;
           this.Age = age;
           this.YearsInCompany = numberOfYears;
        }

        public override void ReceiveBonus(int bonus)
        {
           EndOfyearBonus = 3 * YearsInCompany * bonus;
        }
     }
  }

Kevin

Programming basics : Methods

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Welcome reader,

We’ve gone through a lot of the core fundamentals of programming with C#. We’ve seen how to evaluate conditions in our program flow and different ways to repeat a block of code with the help of loops. We’ve seen different notions that can help us to really understand how a software program works with the basics.

At first, when we create a console application, we dwell in the fact that the software application has X lines of code. Sure, having a lot of code seems fun, we look like we know what we’re doing. As fun as it may look, a lot of code is really hard to maintain. While we may think that as soon we’re doing writing a software that it’s done, we may have to come back in a few days or months to improve its functionality.

But that’s not the topic of this post. What we’ll learn today is to create methods. Using methods can reduce the code we need to have in the main method, which was seen in a previous example. A software program runs from the main method which will do exactly what our program needs to do. Sounds weird huh ? Code can exist outside the main method, but to be used, the code must be called in the main method.

Basically, a method helps us to not have to repeat code, and that’s something we should always try to achieve while we are developing something. Why would we want to do that ? Because if a piece of code has a bunch of errors, if we duplicate it in several places, we’ll have to look for all those pieces and correct what was wrong. That is not a good practice, we should aim to not do that.

Methods can be simple, we could only need something which would take the name of a person as an input and print a welcome message. Like this


static void PrintWelcomeMessage(String personName)

{

    Console.WriteLine("Welcome in this software application, {0}", personName);

}

With methods, the naming convention changes. The first letter is upper-case. Moreover, the first word of the method has to be a verb, it shows exactly what the method is trying to achieve. In the previous example, the method is “PrintWelcomeMessage”. It’s easy to understand that the method is printing a welcome message and takes a parameter, a string data type. For now, we’ll won’t focus on the static keyword.

More than just the naming convention, methods, as it was mentioned earlier, can take, what we call, parameters. Sometimes, they don’t. Parameters are values that are placed inside the parenthesis. We have to define the type of the parameter and give a name to the variable, like we always have done before.


static void PrintWelcomeMessage(String personName, int ageOfPerson)

{

    Console.WriteLine("Welcome in this software application, {0}", personName);
    if(ageOfPerson>18)
    {
       Console.WriteLine("You are a minor");
    }else{
         Console.WriteLine("You are not a minor");
    }

}

We haven’t discussed another keyword that has appeared in this post, “void”. Void means that the method won’t return any value after it has reach its end. When we’re using methods, we can decide if we want a method to return something, like the result of a computation. We’ll try out a class(classes will be discussed at length in a later post) which is given by the .NET framework, Math. Thanks to this previous class, we can use different math skills which we could have learned before such as square root, sinus or power.


static double[]  ComputeDifferentValues(int a, double b, double c)

{

     double[] myMathComputedArray =  new double[5];

     for(int i=0;i<5;i++){

        switch(i){

          case 0:

                myMathComputedArray[i]= Math.sqrt(a+b+c);  //This will compute the square root of(a+b+c)

                break;

          case 1:

                myMathComputedArray[i]=Math.pow(a,b); //This will compute a power b

                break;

          case 2:

                myMathComputedArray[i]=Math.Abs(a-b-c);//returns the absolute value of a double floating-point number

                break;

          case 3:

                 myMathComputedArray[i]=Math.Ceiling(b);//returns the smallest int (integer) value that is greater than or equal to the double value that was passed as a parameter

                break;

          case 4 :

                myMathComputedArray[i]=Math.Sin(a); //returns the sine of the given angle

                break;

        }

     return myMathComputedArray;

}

As we could have seen in the last code sample, when we perform any kind of operation and we want to have it later, we have to return what we which to have. In this case, we used a switch to store different values in an array. When we were done, we used the return keyword, which return the variable we which to return we need it.

We have covered basics to some point. There is a lot we need to know before we can get better. But now, with what we know at the moment, a lot can be achieved.  We’ll see how to create console applications in order to resolve issues with all we’ve seen so far in later post such as creating a menu for a user who wishes to withdraw money from his bank account or how to manage an inventory.

Programming basics: what are strings ?

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Welcome reader,

When we first talk about, it was mentioned that the String data type were to be discussed in a later post. So what exactly are String ? If you remember, we have the char data type, which is used to store a single character inside a char variable. Sometimes, we need to manipulate more than just one character. What previous programmers did to get around this issue was to use Arrays.

Arrays can really simply your work when you have to store a lot of information into your program. You have to look at arrays like entities in which you can store multiple variables of the same data type in a single structure.

In programming,  an array type is use to describe a collection of elements of the same data type like it was said before.  Each element in the array can be access with identifying keys (indices). Usually, when we have a ten values that we want to store, we start counting from value 1 to value 10. In computer science, we start counting starting from 0.  A quick trick to know the last identifying key of your array would be to take its length and reduce it by one. The length of an array is defined as how many elements it can possibly store.

This is how arrays works :

Array in Java Comparision

Something must be kept in mind while we’re using arrays : they are static. STATIC. Usually, when we use variables, the value that is stored in the variable can be modified at any time. When we initialize an array, we either directly store the values it will hold or we give the maximal length of the array. If ever we were simply initialize the array with its maximal length, every value in the array will either be undefined (null) or 0. Null values will be aborted in a later post. We’ll see below how to do such things.

arrays


//this is how to initialize an array of int

//With a maximal length of 10

int[] anIntArray = new int[10];

//the new operator can be omitted if an initializer is provided

int[] arrayOfNumber = {1,3,5,7,9,11,13,15,17,19};

//once we initialize an array, its maximal length can't be CHANGE !

//but the values that are stored can be modified.

//Storing values in an array can be achieved with the help of their indices

anIntArray[0]=1;

anIntArray[1]=2;

//so on and so on until we reach the last indice

//Storing values can be achieved with the help of loop

//Example with a for loop and using the size (maximal length) of the array

for(int i=0; i<anIntArray.size();i++)

{

anIntArray[i]=(i*2)+3;

//Accessing the indices of the array to store a value, one at a time

}

Arrays have a lot of potential when we are developing a software application. In fact, as it was mentioned before, the programmers of the old had to use char array to store what have become String value. We’ll see an example how to create a char array and showing the values of the array for the user.

4

char chABC[26]= {'a','b','c','d','e','f','g','h',i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'};

for(int i=0;chABC.size();i++){

Console.Write(chABC[i]);

}

Now, we can directly manipulate the String class ( more on classes and null later).  Doing so, we can directly store input from the end-user like a name  or an address. We can also have information which will never change to present to the end-user such as “warning, you are entering a dangerous zone, please make sure you know what you’re doing or get out of here.”

What’s particular with the string data type is the following : it is immutable. That’s kind of big word for beginners and it is somehow kind of hard to understand at first. Like arrays, strings cannot be modified. But not in the same way as arrays. When a string data type is initialized, it holds a certain value. If along the way, a programmer was to modify the same string variable, it would not cause any problems. But, it would be as if the programmer created a new string. A string only points to certain memory at a time, if the value is modify, it will never be the same string even though it is the same variable.  After a while, what is called extension methods are used to modify data type that are immutable such as string. This is a more advanced topic and will be discussed at length in a later post. We’ll see below an example how of to initialize a string variable


string ourFirstString="This is a string variable. We'll be able to show text with it to end-users of our software application";

Console.WriteLine(ourFirstString);

Kevin

Programming basics : Using loops

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Welcome reader,

This blog post will cover the use of loops. Loops are used to repeat the same operation(s) at least once. Usually, most programs you can think of will need this kind of functionnality. We can use loops to go through data or let a program start from the start, they can even be use when we need to compute data. In order to execute a loop, a condition must be validate, which was why we had to know how to manage the program flow of a software application.

The first loop we’re going to see is the while loop. In order to know what is happening in a loop, we must first know how to write a loop. When using a while loop, we’re telling the computer the following statement: while the following condition is true, please perform all the stuff that is inside the loop. It is thanks to this condition that the loop will know when it has to stop the looping operation. While this must sound like an easy task to do, this is a well known issue for beginners: infinite loops. For example, like we saw earlier with the comparison operators, if we were to tell while the value of 1,  the while loop will never know when to stop because the value, in the condition, does not change. We’ll see below how to write a while loop with an example :


char selectedAnswerFromUser='Y';

while(selectedAnswerFromUser== 'Y') //We are evaluating the condition the the    equality operator and not the assign operator !

{

Console.WriteLine("Would you like to stop this loop? Please press y for yes or n for no");

selectedAnswerFromUser =Console.ReadLine();

if(selectedAnswerFromUser== 'n')

{

Console.WriteLine("GoodBye ! ");

}

if(selectedAnswerFromUser !='y' || selectedAnswerFromUser != 'n')
{
   Console.WriteLine("Please, you can either press the y or the n letter!");

}

To continue, there is a similar loop to the while loop; it is called the do while loop. The single difference is that the do while will be performed at least once even if the condition is not true. That is the difference between the while and do while loop. We’ll see below an example of the do while loop :


int a=2;

int b=5;

do{ //We start the loop without giving a condition, it will be given below

a++; //The ++ operator tells the computer to increment the value of the a variable by one

Console.WriteLine(a); //This will print the value of a while we are performing the loop

}while(a<b); //in the do while loop, after giving your condition, finish your statement with the ';'

While we are using loops, you can also use variables to count the number of times the loop will perform. We saw the ++ operator earlier, which is meant to increment the value of a variable by one after the line has been read. We have an equal operator in case we want to decrease the value of a variable; the — operator. Here where it gets tricky: depending on which side you put the operators, the have different effects :

  1. variable++ :  The value we use is the value before the incrementation (Postfix incrementation)
  2. ++variable:The value of the variable we’re using is the value after the incrementation (Prefix incrementation)
  3. variable–: The value we use is the value before the variable decreases by 1(Postfix decrementation)
  4. –variable: The value we use is the value after the variable decreases by 1 (Prefix decrementation)

Thanks to those, we’ll now see how to create a condition in a while loop.


int a=5;

while(a<20) { ++a; Console.WriteLine("This the value of the a variable : {0}",a); //This the modulo operator. //It divide the variable a by 2 and looks for remainders //if there are none ->the value will be 0

// else -> We'll see the remainder

if( a%2 == 0 )

{

Console.WriteLine("The value of a will be diminish by 2. This is the value of a now: {0},a);

a=a-2;

}else{

int remainderFromModulo=a%2;

Console.WriteLine("This is the remainder of the modulo : {0}",remainderFromModulo);

}

a=a+3;

}

The last loop we’re going to see in this post is called the for loop. This loop is different from the previous ones that we first saw. This kind of a loop is used when we know exactly the number of times we are going to repeat the block of code until the condition becomes false. The structure is a bit different as we can see below :


for(int i=0;i<5;i++)

{

//do stuff

//when the i variable has the value of 5, then the for loop will stop its iteration

}

In the for loop, we first have to initialize which variable is used to iterate, but it does not have to hold the value of 0. Then, after the semi-colon, we have to give a condition to the loop, which, like we know, use to know how long we have to iterate. And finally, we have to specify if the value of this variable is going to increase or to decrease. Also, we don’t have to increase/decrease by the value of 1. It was used to serve as an example.

Kevin

Programming basics : variables

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Welcome reader,

This is the first part of a mini-serie to introduce the basics of programming with C#. Don’t forget to look at my GitHub account. I haven’t decide yet, but surely I will create a project which will resume every topic that I’ve talked about during the Programming basics serie.

So, we’re finally there, will start talking about the programming at last! In this serie, I assume that you’ll have already downloaded your IDE( if you don’t know what’s an IDE, please go read my blog post about IDEs) on your machine. Like I have mentionned before, I’ll be using the Visual Studio Community Edition IDE in this blog.

The introduction to programming start with a fundemental topic : variables. When you are programming, you are telling your machine exactly what you want it to achieve. In order to do so, you have to manipulate data directly on your machine, and when you’ll be running your software application(more of running later), the code that you’ve given will look like this:

0101010 0101 010101 01010

For the untrained eyes, it’s only 0s and 1s. But that is called binary code. This is what your machine use to achieve an operation that you have order it to do.  Even when you are on your user interface of you operating system, you are telling your computer what to achieve for you such as

Opening a folder

Save a file

With the IDEs,  our life is easier, we don’t need to actually manipulate data on the computer with binary code, we use variables. What this means is this: variables points to different parts of the computer memory. In short, variables have a name and a value.They hold different kind of data which can be manipulate and consume by a programmer in order to achieve his goal. Below, you’ll be able to see all the variables that are accessible in most programming languages:

  • byte – 8 bits
  • short – 16 bits
  • int – 32 bits
  • long -64 bits
  • float – single precision 32 bit floating numbers
  • double – double precision 64 bits floating numbers
  • decimal – 16 bits
  • bool – boolean value (true/false)
  • char – holds a character
  • String (it will be discussed in a later post)

From byte to long, these represent integer values such as 0, 100, 200. We have access to different kind of integer values, and when you are programming, you have to choose carefully the exact type you need because each type has its own weight in bit. The more you use, the bigger the software application will be. To understand the difference between the type of integer you can choose, you will find below the range of values each one has:

  • byte [0,255]
  • short [-32768,32767]
  • int [-2147483648,2147483647]
  • long [-9223372036854775808,9223372036854775807]

For example, if you create a software application which will only hold employees ages, using long variables because of their weight. Rapidly, in an application with around a million employees, the software would be heavy to process because you’re using the wrong type of data. In this case, knowing that the human’s span life is around 80 years, using the byte type would be much better. While using variables, you should always use your judgement in order to be memory efficient. Lower, you’ll be able to find an example of a byte variable containing the age of an employee:


byte employeeAge=30;

As you can see, when using a variable, the variable’s name is on the left and the value,which will be assigned, is on the right.  To continue, the float,double and decimal types should be use only when you to consume data which contained the full value of number like 1.25.


int firstValue=1.25; //firstValue will only be 1 because it is an integer
float secondValue=1.25; //secondValue will be 1.25

Console.WriteLine(firstValue);//Will display the value of 1
Console.WriteLine(secondValue); //Will display the value of 1.25

Upward, you can see some code sample showing the use of two variables and C# function(more on functions later) in order to display data to the screen. There’s quite a lot going on in this sample, the part with the double slash is called comments. Comment will be discussed in the next part of this serie. Moreover, as you can see, the names of the variable don’t really represent anything. When using variables, the names you use should always be meaningful. By always doing so, you’ll be able to understand the code you’ve written a while back faster without, or almost, need of comments.

To finish, the char type can only hold a character as a value. A character can be anything such as a alpha or numerical character. The char data is assigned with single quotes. You can see an example below.


byte charVariable='1';

To wrap up, variables have a meaningful name and a value. When using variables in your software application, you should make sure to always use the right type in order to be memory efficient.

Kevin

Software Version Control & Git

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Before going into coding, I wanted to talk about software version control and the perks of using it in your daily life. The version control, simply, is a repository (storage location). In the repository, the source code, and other files,  from a software project. Every changes made to the software project will be track along with the user’s name who made the change.

While using version control, users are allowed to roll back to previous versions of the project. This means that if ever a version in the repository was problematic, a given user would be able to select a working version. The repository are needed, I would say vital,  when doing a collaborative development work. Being able to track what each and everyone did on the team is a huge bonus. Plus, since it is online, there’s no need of having a dedicated server which would have to contain all the information of the project.

For developers, a software is never done. The project is always growing, we always want to find different ways to improve a software and make it better. While doing so, they’ll want to compare previous versions to understand the many changes that happen in a software. Like it was mentioned earlier, every version is tracked so, it easy to perform such a task.

I’m telling you about this because I consider this as an important subject to talk about in the dev world. Plus,  while I’m talking about different topics in this blog, when I’ll create mini-series to go deeper into a subject, the software application will be available to you, the reader. There are different ways to exploit the software version control. In my case, I’m using https://github.com/.

With GitHub, after you’ve created your account, you’ll be able to create public and private repositories. The benefit of creating your repositories in the private mode is to just allow  yourself and the allowed collaborator to access your software project. When you create a public repository, any given user will be able to access your project.

To have an easy access to any versions of a GitHub project, I’ll introduce you to an user interface of GitHub : SourceTree. It is a software that can be used by Windows and OS X users. With the SourceTree software, you’ll be able to “clone” a repository with the HTTPS url link from the project. You’ll be able to find the software with this link http://www.sourcetreeapp.com/

This being said, you’ll have accessed to my public repositories with link https://github.com/Kavignon. In brief,  repositories are tracked storage location which provide users the ability of reverting on a different version of a project or any file of the project. At first, you can ask yourself why you’re actually doing this, but later you’ll see you can’t live without it! It is really helpful!

Kevin