C language was developed between 1969 and 1973 by Dennis Ritchie and Ken Thompson at Bell Labs. It was originally created to re-implement the UNIX operating system. The first example program that appeared in the book "The C Programming Language" by Ritchie and Kernighan (K&R) was named "Hello, World!". C language includes lowercase and uppercase letters, decimal digits, and graphic characters in its character set and has 32 keywords. It is widely used today for system programming and website programming.