The C programming language is to powerful and universal to ignore. Many (most?) popular languages today have something in common with C, if they aren’t direct descendants! C can be written and compiled on a number of platforms, and its many uses make it a considerably flexible language.
C’s firstborn child, C++, is an object–oriented extension to the parent language.
CGI stands for Common Gateway Interface. CGI is a method of programming web servers, and C is a welcome member of the family of languages that are able to use CGI standards.