Computer Programming – A Complete Tutorial
Get ready to dive deep into the world of Computer Programming and know all about the Basics of Programming in detail.
Computer Programming is a set of instructions, that helps the developer to perform certain tasks that return the desired output for the valid inputs.
Given below is a Mathematical Expression.
Z = X + Y, where X, Y, and Z are the variables in a programming language.
If X = 550 and Y = 450, the value of X and Y are the input values that are called literals.
We ask the computer to calculate the value of X+Y, which results in Z, i.e. the expected output.
How Do Computers Work?
A computer is a machine that processes information and this information can be any data that is provided by the user through devices such as keyboards, mouse, scanners, digital cameras, joysticks, and microphones. These devices are called Input Devices and the information provided is called input.
The computer requires storage to store this information and the storage is called Memory.
Computer Storage or Memory is of Two Types.
- Primary Memory or RAM (Random Access Memory): This is the internal storage that is used in the computers and is located on the motherboard. RAM can be accessed or modified quickly in any order or randomly. The information that is stored in RAM is lost when the computer is turned off.
- Secondary Memory or ROM (Read-Only Memory): Information (data) stored in ROM is read-only, and is stored permanently. The ROM stored instruction is required to start a computer.
Processing: Operations done on this information (input data) is called Processing. The Processing of input is done in the Central Processing Unit which is popularly known as CPU.
Output Devices: These are the computer hardware devices that help in converting information into human-readable form. Some of the output devices include Visual Display Units (VDU) such as a Monitor, Printer, Graphics Output devices, Plotters, Speakers, etc.
A developer can analyze the problem and come up with simple steps to achieve a solution to this problem, for which he/she uses a programming algorithm. This can be compared to a recipe for a food item, where ingredients are inputs and finished delicacy is the output required by the client.
In the development environment, the products, software, and solutions can be designed as scenarios, use cases, and data flow diagrams
Basic Programming Concepts
Developers should have essential knowledge on the following concepts to become skilled in Computer Programming,
#1) Algorithm: It is a set of steps or instruction statements to be followed to accomplish specific tasks. A developer can design his algorithm to achieve the desired output. For Example, a recipe to cook a dessert. The algorithm describes the steps to be followed for completing a specific task, but it does not say how to achieve any of the steps.
#2) Source code: Source code is the actual text that is used to construct the program using the language of choice.
For Example, it is mandatory to have the main method in Java and the text used is as shown below.
#3) Compiler: Compiler is a software program that helps in converting the source code into binary code or byte code, also called machine language, that is easy for a computer to understand, and can be further executed using an interpreter to run the program.
#4) Data Type: Data used in the applications can be of a different type, it can be a whole number (integer), floating-point (decimal point numbers), characters or objects. For Example, double currency = 45.86, where double is a data type used for storing numbers with decimal points.
#5) Variable: Variable is a space holder for the value stored in the memory and this value can be used in the application. For Example, int age = 25, where age is a variable.
#6) Conditionals: Knowledge of how to use a certain condition, such that a set of code should execute only if a certain condition is true. In case of a false condition, the program should exit and should not continue the code further.
#7) Array: Array is the variable that stores elements of a similar data type. Knowledge of using an array in coding/programming will be a great benefit.
#8) Loop: Loop is used to execute the series of code until the condition is true. For Example, in Java, loops can be used as for loop, do-while, while loop or enhanced for loop.
The code for loop is as shown below:
#9) Function: Functions or methods are used to accomplish a task in programming, a function can take parameters and process them to get the desired output. Functions are used to reuse them whenever required at any place repeatedly.
#10) Class: Class is like a template that contains state and behavior, which corresponding to programming is field and method. In Object-Oriented languages like Java, everything revolves around Class and Object.
Essentials Of A Programming Language
Just like any other language we use to communicate with others, a programming language is a special language or a set of instructions to communicate with computers. Each programming language has a set of rules (like English has grammar) to follow and it is used to implement the algorithm to produce the desired output.
Top Computer Programming Languages
The below table enlists the top Computer Programming Languages and their applications in real life.
|Programming Language||Popularity||Practical Applications of Languages|
|Java||1||Desktop GUI application (AWT or Swing api), Applets, online shopping sites, internet banking, jar files for secured file handling, enterprise applications, mobile applications, gaming software.|
|C||2||Operating Systems, Embedded systems, Database management systems, Compiler, gaming and animation.|
|Python||3||Machine learning, Artificial Intelligence, Data analysis, face detection and image recognition Software.|
|C++||4||Banking and trading enterprise software, virtual machines and compilers.|
|Visual Basic .NET||5||Windows services, controls, control libraries, Web applications, Web services.|
|C#||6||Desktop applications like a file explorer, Microsoft office applications like Word, Excel , Web browsers, Adobe Photoshop.|
|PHP||8||Static and dynamic websites and applications, Server side scripting.|
|SQL||9||Querying database, CRUD operations in database programming, creating a stored procedure, triggers, database management.|
|Objective – C||10||Apple’s OS X, iOS operating system and APIs, Cocoa and Cocoa Touch.|
Let’s see how to select a programming language.
The selection of particular programming languages depends on many factors such as:
- Targeted Platform and Project/Solution Requirement: Whenever a software solution provider comes across the requirement, there are many options to choose an appropriate programming language. For Example, if a user wants the solution to be on mobile, then Java should be the preferred programming language for Android.
- Influence of Technical Partners with the Organization: If Oracle is a tech partner with the company, then it is agreed to implement software marketed by Oracle in the solution for every project and product developed. If Microsoft is a tech partner with the company, then ASP can be used as a development framework for building web pages.
- Competency of available Resources & Learning Curve: The developers (resources) should be available and competent to quickly learn the selected programming language so that they can be productive for the project.
- Performance: The selected language should be scalable, robust, platform-independent, secure and should be efficient in displaying results within the acceptable time limit.
- Support from the Community: In the case of open-source programming language, the acceptance, and popularity for the language as well as online support from the growing support group should be available.
Types Of Computer Programming Languages
Computer Programming language can be divided into two types i.e. Low-level Language, and High-level Language.
#1) Low-level Language
- Hardware dependent
- Difficult to understand
Low-level Language can be further divided into two categories,
- Machine Language: Machine dependent, difficult to modify or program, For Example, every CPU has its machine language. The code written in machine language is the instructions that the processors use.
- Assembly Language: Each computer’s microprocessor that is responsible for arithmetic, logical and control activities needs instructions for accomplishing such tasks and these instructions are in assembly language. The use of assembly language is in device drivers, low-level embedded systems, and real-time systems.
#2) High-level Language
- Independent of hardware
- Their codes are very simple and developers can read, write and debug as they are similar to English like statements.
High-level Language can be further divided into three categories.
- Procedural Language: Code in the procedural language is a sequential step by step procedure, that gives information like what to do and how to do. Languages such as Fortran, Cobol, Basic, C, and Pascal are a few examples of procedural language.
- Non-procedural Language: Code in non-procedural language specify what to do, but does not specify how to do. SQL, Prolog, LISP are a few examples of non-procedural language.
- Object-oriented Language: Use of objects in the programming language, where the code is used to manipulate the data. C++, Java, Ruby, and Python are a few examples of Object-oriented language.
Basic Operations Of A Programming Environment
Five basic elements or operations of programming are listed below:
- Input: Data can be input using the keyboard, touch screen, text editor, etc. For Example, to book a flight, the user can enter his login credentials and then select a departure date and return date, the number of seats, starting place and destination place, Name of Airlines, etc, from desktop, laptop or mobile device.
- Output: Once authenticated, and upon receiving the request to book the tickets with the mandatory inputs, a confirmation of booking for the selected date and destination will be displayed on the screen, and a copy of the tickets and invoice information is sent to the user’s registered email id and mobile number.
- Arithmetic: In case of flight booking, update of the number of seats booked and those seats need some mathematical calculations, further name of the passenger, no. of seats reserved, date of journey, journey start date, and starting place, destination place, etc. should be filled into the airlines server database system.
- Conditional: It is required to test if a condition is satisfied or not, based on the condition, the program may execute the function with parameters else it will not get executed.
- Looping: It is required to repeat /perform the task until the condition holds. Types of loops can be While loop, Do-while loop, For loop.
Necessary Prerequisites/Skills Required For Programming
#1) Self Reliance: To succeed in coding, you should develop a confidence in yourself, control your impatience, frustration and should refrain from being dependent on someone else to help you in solving your technical problems, rather you should be self-reliant and keep faith on your capabilities, monitor your efforts and remain optimistic and perseverant in learning.
#2) Language: It is an individual’s choice to decide which programming languages he/she should learn. A programming language should be selected based on its acceptance in the various domains in software industries. Object-oriented languages like Python and Java, which are free & open-source are widely accepted and used by Google, Yahoo, and NASA.
#3) Logic: As a developer or tester, to excel in the programming language, one must always have conditional and logical thinking. It can be improved as we improve our muscles, there are a few sites where one can prepare and improve logical thinking and prepare for programming language.
#4) Attention to Detail: A conscientious and alert person with an eye for details will check his/her work for minute details and this will prevent any syntax error, verify if any steps like unit testing or including API /classes, miss associated jar or class files. For some people, meditation might help to improve focus and concentration while for others taking a walk or playing some mind games might help. You need to find out what works for you.
#5) Abstract Thinking: During sprint meeting in an agile environment, the ability to think out of the box, or see things from different angles/perspectives, help to uncover scenarios for requirements and design considerations. This can be improved by a discussion with others.
#6) Patience: At times, it happens as you write a code, for which you are confident about, verified it a couple of types, it works in your machine, but after integration the code snippet does not work, all the effort to identify the fault go in vain, you feel stressed out, frustrated and feel like good for nothing.
During such times, your ability to overcome the situation, try again from scratch and develop patience will prove the developer to be more mature and he/she gets appreciated for the ability to work under pressure environments like releases and acceptance testing or during client demos.
#7) Strong Memory: Being able to understand and visualize the high-level design, data flow, algorithm, data structure, how they interact with each other will separate you from an average coder. Meditation techniques and memory exercises can help with this as well.
How To Start Learning Computer Programming?
As a human, you should have the habit to introspect daily and identify what you have done today, how can you improve yourself, what steps or precautions you will take to avoid difficult situations.
Similarly, consider the below points before learning computer programming.
- Be honest and think about why you want to learn computer programming.
- What is your goal, what will you accomplish in your dream of learning programming?
- Check out some interactive tutorials to get familiar with a programming language. w3schools is good to start understanding many programming languages, and w3resource is good to learn SQL queries interactively.
- Try out some online courses i.e. give a try to Udemy
- Learn Data Structures and Algorithms.
- Make a project using a selected programming language.
- Attempt some certification, and this will make you more confident, knowledgeable and competent.
Where Can We Apply The Skills Of Programming?
- Ability to Communicate: Communication is an extremely essential quality wherein, you can explain your plan, discuss your doubts, improve your thoughts and exchange information from your superior and your team member. A good communicator can understand and explain the tasks performed in daily reporting, find out how can you improve your thoughts and clear your doubts. During the agile standup meeting & sprint meets, you can communicate the plan of action and can lead the team.
- Problem-solving: Accepting challenges and accomplishing difficult tasks will build problem-solving skills and this is a prerequisite for a good developer. During development, you may encounter various issues of understanding the business logic and implementing them into your code, integration of the code with application, compatibility issues and many more challenges. Your problem-solving skills will help you to sail through the most critical situations.
- Collaboration/Teamwork: Collaboration skills enable you to work with the team members to accomplish some tasks effectively and thereby improve productivity.
Working in a team at times can result in conflict, due to attitude issues. Hence, by understanding the goal to get better products or improve productivity, anyone can play the role of an excellent team player role.
Career Options For Programmers
The career options as a programmer or software developer are many.
The areas or positions for computer programmer are as follows:
- Web Developer
- UI Developer
- User Experience Designer
- SQL Developer
- Quality Assurance
- Automation Test Engineer
- Software Engineer at Test
In the Software Development department his/her responsibilities include the following duties:
- Manage project software delivery lifecycle, that includes planning, design, building, testing, and deployment within the company’s planned delivery framework.
- Basic knowledge in Networking, ability to work on Integrated Developer Tools such as Eclipse, NetBeans, Atom, etc.
- Should have hands-on working experience with at least one of the CI tools such as Jenkins, Gitlab, Bamboo, etc.
- Should able to use Linux / Unix scripts and shell scripting.
- Excellent communication and people skills.
- Should be a good Team player as well as an Independent Contributor.
- Understanding of agile development environment.