In this note, I will argue for the importance of learning the C programming language despite its lack of trendiness in modern software development. Four primary reasons for this stance:

  1. Prevalence: C remains one of the most commonly used programming languages, particularly outside the Silicon Valley’s web and mobile startup environments.
  2. Influence: Many contemporary programming languages are heavily influenced by C, making an understanding of C beneficial for mastering other languages.
  3. Fundamental Understanding: Learning C helps programmers think like a computer, offering a deep understanding of how computers work at a fundamental level. This includes insights into computer architecture and assembly language.
  4. Tooling and Performance: Most software development tools, interpreters, and critical system components are written in C or C++. This includes Python’s CPython implementation, Ruby’s reference implementation, and many JavaScript engines.

Abandoning C means losing out on an in-depth comprehension of the systems and tools that underpin modern software development. This includes understanding memory layout through data structures like hashmaps and dynamic arrays, grasping operating system internals, and comprehending network stack implementations.

While many engineers may excel without deep knowledge of C, those aiming to do groundbreaking, high-impact work will find mastering C indispensable.