Programming in C Language - Lecture 1 Notes

Introduction to Programming

• Purpose of Programming: To communicate tasks to computers, which can only understand binary (0s and 1s).
• What is a Program?: A sequence of instructions that directs the computer to perform computational tasks.

Need for Programming

• General-Purpose Machine: A computer can perform any computational task but needs instructions to do so.
• Communication with Computer:
  • Direct communication (e.g., asking to add numbers) is not possible.
  • Use of programming languages to write instructions that the computer can understand.

Computer Language

• Binary Language: The only language understood by computers (0s and 1s).
• Importance of Programming Languages:
  • They convert human-readable instructions into binary.
  • Examples include high-level languages like C, C++, and Java.

Types of Programming Languages

• Low-Level Languages: Machine languages (binary) and assembly languages.
• High-Level Languages: Easier for humans to understand and write (e.g., C).
  • High-level languages allow for portability—programs can run on different machines with minimal changes.

Overview of the C Language

• Development: Created by Dennis Ritchie in 1972 at Bell Laboratories as a successor to the B language.
• Purpose: Initially developed to write the Unix operating system.
• Characteristics:
  • C is a system programming language.
  • Widely used in developing software applications (e.g., UNIX, device drivers, and Android core libraries).

C Language Features

• Standardization: Standardized by ANSI in 1989, hence known as ANSI C.
• Compiled Language:
  • Requires a compiler to convert C programs (with .c extension) into machine code (object files).
  • The CPU executes the object code after it is compiled.

Key Processes in C Programming

• Compilation Process:
  • Write code in C, compile it using a compiler to generate object code (machine language).
  • Involves linkers and loaders that prepare executable files for CPU execution.
• Interpreters: Convert high-level programs to object code, but differences from compilers to be discussed in future sessions.

Conclusion

• Next Steps: Upcoming videos will cover the execution process and the roles of compilers, linkers, and loaders in detail.