Learn C - 100 Code Examples & CST Typing Practice Test
C is a general-purpose, procedural programming language that provides low-level access to memory, efficient performance, and a foundation for system and application software development.
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Learn C with Real Code Examples
Updated Nov 27, 2025
Architecture
Compiled language with direct translation to machine code
Supports procedural modular design
Memory and hardware accessed via pointers and addresses
Standard libraries provide I/O, string, math, and utility functions
Preprocessor handles macro expansion and conditional compilation
Rendering Model
Source code written in .c files
Preprocessor handles macros/includes
Compiler translates code to machine instructions
Linker combines object files and libraries
Executable runs on target hardware
Architectural Patterns
Modular programming using functions
Structs for composite data
Pointers for memory and hardware access
Preprocessor for compile-time directives
Manual memory management via malloc/free
Real World Architectures
Embedded firmware for microcontrollers
Operating system kernels and drivers
High-performance scientific computation
Network and database systems
Compilers, interpreters, and system utilities
Design Principles
Procedural programming
Efficiency and performance
Low-level memory control
Portability across platforms
Minimal runtime and standard library
Scalability Guide
Use efficient algorithms and data structures
Manage memory and resources carefully
Modularize code for maintainability
Use compiler optimization flags
Profile and optimize performance-critical sections
Migration Guide
Update code to comply with C99/C18 standards
Replace deprecated functions (e.g., gets -> fgets)
Test compilation on new compilers
Verify pointer and memory usage
Refactor for portability and maintainability
Frequently Asked Questions about C
What is C?
C is a general-purpose, procedural programming language that provides low-level access to memory, efficient performance, and a foundation for system and application software development.
What are the primary use cases for C?
Operating system kernels (e.g., Linux, Windows). Embedded systems and microcontrollers. Device drivers and hardware interfaces. Compilers, interpreters, and runtime systems. High-performance computing and real-time applications
What are the strengths of C?
High performance and low overhead. Portable across platforms. Fine control over system resources. Large ecosystem and mature tooling. Foundation for many other programming languages
What are the limitations of C?
No built-in memory safety (manual management required). Lacks object-oriented features. Limited standard library compared to modern languages. Error handling via return codes, no exceptions. Steeper learning curve for beginners due to pointers and memory
How can I practice C typing speed?
CodeSpeedTest offers 100+ real C code examples for typing practice. You can measure your WPM, track accuracy, and improve your coding speed with guided exercises.