Introduction to Programming

COMPUTER PROGRAMMING is defined as a process of developing and implementing various set of instructions given to the computer to perform a certain predefined task. Computer Programming is easy if it is appropriately managed. There are many computer programming languages available so finalizing the right language is not an easy task.

Basic of programming

Any other Human Languages (German, Spanish, Russian, etc.) are made of several elements like nouns, adjective, adverbs, propositions, and conjunctions, etc. So, just like English, Spanish or other human languages, programming languages are also made of different elements.

Basic components of program

Just like human languages, programming languages also follow grammar called syntax. There are certain basic program code elements which are common for all the programming languages.
Most important basic elements for programming languages are:

• Programming Environment
• Data Types 
• Variables
• Keywords
• Logical and Arithmetical Operators
• If else conditions
• Loops
• Numbers, Characters and Arrays
• Functions
• Input and Output Operations

Applications of computer programming languages

Python:

Web and internet development, scientific and numeric application ,Desktop GUIs, Business application. it is widely using AI and machine learning space.

R

Data science projects, statistical computing , machine learning

JavaScript

You just include web/mobile app development,game development and desktop app development.

Swift

 Swift specially designed language which work with Apple's cocoa and cocoa frameworks to create all type of iOS apps.

C++

C++ is widely used in game development, advanced computation and graphics compile.

C#

Widely used in Enterprise cross applications development , web applications.

PHP

Web development,content management system,E-Commerce application.

SQL

Using any database

Go

Console utilities ,GUIs application and web 

Computer programming is the process of designing and building an executable computer program to accomplish a specific computing result . Programming involves tasks such as: analysis, generating algorithms , profiling algorithms' accuracy and resource consumption, and the implementation of algorithms in a chosen programming language (commonly referred to as coding).

The source code of a program is written in one or more languages that are intelligible to programmers, rather than machine code, which is directly executed by the CPU. The purpose of programming is to find a sequence of instructions that will automate the performance of a task (which can be as complex as an operating system) on a Computer, often for solving a given problem. The process of programming thus often requires expertise in several different subjects, including knowledge of the application domain , specialized algorithms, and formal logic.
Tasks accompanying and related to programming include: testing, debugging, source code maintenance, implementation of build systems, and management of derived artifacts, such as the machine code of computer programs. These might be considered part of the programming process, but often the term software development is used for this larger process with the term programming, implementation, or coding reserved for the actual writing of code.Software engineering combines  engineering techniques with software development practices. Reverse engineering is the opposite process. A hacker is any skilled computer expert that uses their technical knowledge to overcome a problem, but it can also mean a security hacker in common language.

So how computer understand human language ? 

There are many programs designed which acts as translator between machines and humans.
also referred as Translators.
Basically there are three types of translator:
1) Compiler
2) Interpreter
3) Assembler

Translators

Compiler: Compiler converts High level language to Low level language to create executable file and then executes whole file. If any error occurs then it is flagged and compilation stops.

Compiler

Interpreter: Interpreter executes set of code line by line. Just like top to bottom.interpreter execute program until error occurs.

Interpreter

Example: Python
Assembler: Assembler are quiet similar to compiler. It convert code from assembly/low level language to binary code which can be recognized by machine.

Assembler

Modern programming

Quality requirements

The following properties are among the most important:

• Reliability: how often the results of a program are correct. This depends on conceptual correctness of algorithms, and minimization of programming mistakes, such as mistakes in resource management.
• Robustness: how well a program anticipates problems due to errors (not bugs). This includes situations such as incorrect, inappropriate or corrupt data, unavailability of needed resources such as memory, operating system services and network connections, user error, and unexpected power outages.
• Usability: the ergonomics of a program: the ease with which a person can use the program for its intended purpose or in some cases even unanticipated purposes. Such issues can make or break its success even regardless of other issues. This involves a wide range of textual, graphical and sometimes hardware elements that improve the clarity, intuitiveness, cohesiveness and completeness of a program's user interface.
• Portability: the range of computer hardware and OS platforms on which the source code of a program can be compiled/interpreted and run. This depends on differences in the programming facilities provided by the different platforms, including hardware and operating system resources, expected behavior of the hardware and operating system, and availability of platform specific compilers (and sometimes libraries) for the language of the source code.
• Maintainability: the ease with which a program can be modified by its present or future developers in order to make improvements or customisations, fix bugs and security holes, or adapt it to new environments. Good practices during initial development make the difference in this regard. This quality may not be directly apparent to the end user but it can significantly affect the fate of a program over the long term.
• Efficiency/performance: Measure of system resources a program consumes (processor time, memory space, slow devices such as disks, network bandwidth and to some extent even user interaction): the less, the better. This also includes careful management of resources, for example cleaning up temporary files and eliminating memory leaks.

Readability of source code

In computer programming, readability refers to the ease with which a human reader can comprehend the purpose, control flow, and operation of source code. It affects the aspects of quality above, including portability, usability and most importantly maintainability.

Readability is important because programmers spend the majority of their time reading, trying to understand and modifying existing source code, rather than writing new source code. Unreadable code often leads to bugs, inefficiencies, and duplicated code. A study found that a few simple readability transformations made code shorter and drastically reduced the time to understand it.
Many factors, having little or nothing to do with the ability of the computer to efficiently compile and execute the code, contribute to readability.Some of these factors include:

• Different whitespace
• comments
• Decomposition
• Naming conventions for objects (such as variables, classes, procedures, etc.)

Various visual programming language have also been developed with the intent to resolve readability concerns by adopting non-traditional approaches to code structure and display. Integrated development environments (IDEs) aim to integrate all such help. Techniques like Code refactoring can enhance readability.

Algorithmic complexity

The academic field and the engineering practice of computer programming are both largely concerned with discovering and implementing the most efficient algorithms for a given class of problem.  An algorithms expresses resource use, such as execution time or memory consumption, in terms of the size of an input. Expert programmers are familiar with a variety of well-established algorithms and their respective complexities and use this knowledge to choose algorithms that are best suited to the circumstances.

Methodologies

The first step in most formal software development processes is requirements analysis, followed by testing to determine value modeling, implementation, and failure elimination (debugging). There exist a lot of differing approaches for each of those tasks. One approach popular for requirements analysis is Use Case  analysis. Many programmers use forms of Agile software development where the various stages of formal software development are more integrated together into short cycles that take a few weeks rather than years. There are many approaches to the Software development process.
Popular modeling techniques include Object-Oriented Analysis and Design (OOAD) and Model-Driven Architecture (MDA). The Unified Modeling Language (UML) is a notation used for both the OOAD and MDA.
A similar technique used for database design is Entity-Relationship Modeling (ER Modeling).
Implementation techniques include imperative languages (Oop or procedural), functional languages and logic languages.

Measuring language usage

It is very difficult to determine what are the most popular of modern programming languages. Methods of measuring programming language popularity include: counting the number of job advertisements that mention the language, the number of books sold and courses teaching the language (this overestimates the importance of newer languages), and estimates of the number of existing lines of code written in the language (this underestimates the number of users of business languages such as COBOL).
Some languages are very popular for particular kinds of applications, while some languages are regularly used to write many different kinds of applications. For example, COBOL is still strong in corporate data centers often on large mainframe computers, Fortran in engineering applications, scripting languages in Web development, and C in embedded software. Many applications use a mix of several languages in their construction and use. New languages are generally designed around the syntax of a prior language with new functionality added, (for example C++ adds object-orientation to C, and Java adds memory management and bytecode to C++, but as a result, loses efficiency and the ability for low-level manipulation).

Debugging

Debugging is a very important task in the software development process since having defects in a program can have significant consequences for its users. Some languages are more prone to some kinds of faults because their specification does not require compilers to perform as much checking as other languages. Use of a static code analysis tool can help detect some possible problems. 

Normally the first step in debugging is to attempt to reproduce the problem. This can be a non-trivial task, for example as with parallel processes or some unusual software bugs. Also, specific user environment and usage history can make it difficult to reproduce the problem.After the bug is reproduced, the input of the program may need to be simplified to make it easier to debug. For example, a bug in a compiler can make it crash when passing some large source file. However, after simplification of the test case, only few lines from the original source file can be sufficient to reproduce the same crash. Such simplification can be done manually, using a divide-and-conquer approach. The programmer will try to remove some parts of original test case and check if the problem still exists. When debugging the problem in a GUI, the programmer can try to skip some user interaction from the original problem description and check if remaining actions are sufficient for bugs to appear.

Programming languages

Different programming languages support different styles of programming. The choice of language used is subject to many considerations, such as company policy, suitability to task, availability of third-party packages, or individual preference.

Programming languages

Ideally, the programming language best suited for the task at hand will be selected. Trade-offs from this ideal involve finding enough programmers who know the language to build a team, the availability of compilers for that language, and the efficiency with which programs written in a given language execute. Languages form an approximate spectrum from "low-level" to "high-level"; "low-level" languages are typically more machine-oriented and faster to execute, whereas "high-level" languages are more abstract and easier to use but execute less quickly. It is usually easier to code in "high-level" languages than in "low-level" ones.The details look different in different languages, but a few basic instructions appear in just about every language:

• Input: Gather data from the keyboard, a file, or some other device.
•Output: Display data on the screen or send data to a file or other device.
•Arithmetic: Perform basic arithmetical operations like addition and multiplication.
•Conditional Execution: Check for certain conditions and execute the appropriate sequence of statements.
•Repetition: Perform some action repeatedly, usually with some variation.
Many computer languages provide a mechanism to call functions provided by shared libraries. Provided the functions in a library follow the appropriate run-time conventions (e.g., method of passing arguments), then these functions may be written in any other language.

Programmers

Computer programmers are those who write computer software. Their jobs usually involve:

• Coding
• Debugging
• Documentatio
• Integration
• Maintenance
• Requirements analysis
• Software architecture
• Software testing
• Specification

Programmer

How to choose a programming language?

Computer programming is a set of written instructions that the computer follows. These instructions can be written in various languages. Each programming languages have their unique ways of organizing the commands which are called syntax.

Multiple programming languages can help you solve the same programming problem. However, you need to select a language that you feel is relevant to perform your task. If you decide that a language does not suit your business requirement, you can always move on to a new language. Your skill in the chosen language will also be a deciding factor. Expected software system response time, a number of simultaneous users, security, maintains, compatibility with web, mobile, devices are few other factors to consider while choosing a language.