C was developed in the early 1970s and is a popular programming language used for writing system software and applications. It is a high-level language that uses functions and supports pointers to memory locations. Common data types in C include integers, floats, doubles, and characters. Variables are declared with a data type and used to store and manipulate data. C programs contain functions, comments can be added for clarity, and standard input/output functions like printf and scanf are used.