Effective C, 2nd edition, is an introduction to essential C language programming that will soon have you writing programs, solving problems, and building working systems.

The latest release of the C programming language, C23, enhances the safety, security, and usability of the language. This second edition of Effective C has been thoroughly updated to cover C23, offering a modern introduction to C that will teach you best practices for writing professional, effective, and secure programs that solve real-world problems.

Effective C is a true product of the C community. Robert C. Seacord, a long-standing member of the C standards committee with over 40 years of programming experience, developed the book in collaboration with other C experts, such as Clang’s lead maintainer Aaron Ballman and C project editor JeanHeyd Meneide. Thanks to the efforts of this expert group, you’ll learn how to:

Develop professional C code that is fast, robust, and secure
Use objects, functions, and types effectively
Safely and correctly use integers and floating-point types
Manage dynamic memory allocation
Use strings and character types efficiently
Perform I/O operations using C standard streams and POSIX file descriptors
Make effective use of C’s preprocessor
Debug, test, and analyze C programs


The world runs on code written in C. Effective C will show you how to get the most out of the language and build robust programs that stand the test of time.

New to this edition: This edition has been extensively rewritten to align with modern C23 programming practices and leverage the latest C23 features.

Updated to cover C23