C is a powerful system programming language and is commonly used to programme operating systems such as Unix. One of the main advantages of programming in C is that it allows the programmer to write directly to memory. This means that key constructs such as pointers, constants and strings can be used within the memory in an efficient and machine-independent fashion. This free online computer programming course covers topics such as using pointers for direct memory access and manipulation in C, changing the memory address contained within a pointer and introduces constants and string literals. You will learn why pointers contain memory addresses of multi-byte variables, and how to visualise RAM in a new way. This free online computer programming course will be of great interest to IT and software professionals who would like to learn more about this powerful and efficient programming language, and to all learners who would like to learn more about the kind of programming language that is used to develop operating systems.