3. WHAT IS A PROGRAM?
• A program is a Set of Instructions that tells the Computer “What to do and
How to do”.
• A program can be written in many languages like C/C++, C#, Python, Ruby
etc.
4. PROGRAMMING LANGUAGES
• Programming language is a special kind of language that is used to give
instructions to the computer.
• There are three types of languages:
• High-Level Language.
• Middle-Level Language.
• Low-Level Language.
5. HIGH-LEVEL LANGUAGES
• High-Level Languages are English-oriented Human-understandable
languages that are used to make programs.
• Examples of High-Level Languages are C/C++, Java, Python etc.
6. MIDDLE-LEVEL LANGUAGES
• Middle-Level Languages are also human-understandable languages, but
they are a little-bit more complex as they contain some commands of
Machine Language.
• Example of Middle-Level Language is Assembly.
7. LOW-LEVEL LANGUAGE
• Low-Level Language is machine-understandable language and it is very
much difficult for human to understand it.
• Low-Level Language is also called Binary Language or Machine Language
8. HOW DOES COMPUTER UNDERSTAND A
PROGRAM
• The program that we write in a program is in High Level Language(HLL)
i.e. Human understandable language that has the combination of English
and some Special Characters. A computer cannot understand High Level
Language.
• The program written in High-Level Language is called Source Code.
• To understand the Programs written in HLL, computer uses Special
Programs known as Translator.
9. TRANSLATOR
• A translator is a special program written for computers.
• The translator translate High Level and Middle Level Language
instructions into Low Level Language or in Computer Language.
• The program written in Computer/Machine language is called Object Code.
10. TYPES OF TRANSLATORS
• There are two major types of Translators:
1. Interpreter
2. Compiler
11. INTERPRETER
• The interpreter is a type of translator that translates Source Code(Program
written in HLL) into Object Code(program written in LLL) line by line.
• It is a little bit faster than compiler and reports an error immediately after
it has been generated.
• It does not generate a copy of object code.
• It is used by many programming languages such as Java, Python, Ruby.
12. COMPILER
• Compiler is a type of translator that translates the Source Code(Program
written in HLL) into Object Code(Program written in LLL) as a whole.
• It is a bit slower than interpreter, but it is more efficient as compared to
interpreter.
• It creates a copy of object code.
• It is also used by many programming languages such as C/C++, C#.
13. NEXT VIDEO
• Getting started with C++.
• Preprocessor Directive.
• Header Files.
• Libraries.
