1. What is a computer program?
According to wikipedia, a computer program is a collection of instructions that can be executed by a computer to execute a certain task. The instructions are written by following the rules of chosen programming language. Without computer programs, computers are useless.
A computer program contains statements and variables. The statements are instructions to tell the computer what to do with the variables.
2. What is a programming language?
According to wikipedia, a programming language is a formal language comprising a set of instructions that produce various kinds of output. Programming languages are used in computer programming to implement algorithms.
3. What are the different types of programming languages?
- Machine Language
- Uses binary code
- Machine-dependent
- Not portable
- Assembly Language
- Uses mnemonics
- Machine-dependent
- Not usually portable
- High-Level Language (HLL)
- Uses English-like language
- Machine independent
- Portable (but must be compiled for different platforms)
- Examples: Pascal, C, C++, Java, Fortran, . .
4. What is Machine Language?
- The representation of a computer program which is actually read and understood by the computer.
- A program in machine code consists of a sequence of machine instructions.
- Instructions:
- Machine instructions are in binary code
- Instructions specify operations and memory cells involved in the operation
Example:
|
Operation |
Address |
|
0010 |
0000 0000 0100 |
|
0100 |
0000 0000 0101 |
|
0011 |
0000 0000 0110 |
5. What is Assembly Language?
- A symbolic representation of the machine language of a specific processor.
- Is converted to machine code by an assembler.
- Usually, each line of assembly code produces one machine instruction (One-to-one correspondence).
- Programming in assembly language is slow and error-prone but is more efficient in terms of hardware performance.
- Mnemonic representation of the instructions and data
- Example:
Load Price
Add Tax
Store Cost
6. What is High – level Language?
- A programming language which use statements consisting of English-like keywords such as “FOR”, “PRINT” or “IF“, … etc.
- Each statement corresponds to one or multiple machine language instructions (one-to-many correspondence).
- Much easier to program than in assembly language.
- Data are referenced using descriptive names
- Operations can be described using familiar symbols
- Example:
Cost = Price + Tax;
7. What are some of the most popular programming languages?
There are many programming languages in the world. The term programming language usually refers to high – level languages. Here’s a list of the most popular programming languages in the recent years:
- Python
- Java
- C / C++
- JavaScript
- Go
- R
- Swift
- C# .NET
List of Sources and References:
- CMU Lectures, Introduction to Computer Programming
- MIT Open Courseware, Introduction to Programming Langages