The C90<\/a> standard, formally known as ISO<\/a>\/IEC 9899:1990, represents the inaugural international standardization of the C-Programming-Language<\/a>. It was based heavily on the ANSI<\/a> X3.159-1989 specification, which is frequently called C89<\/a>. This formalization superseded the informal K-and-R<\/a> standard established by Dennis-Ritchie<\/a> and Brian-Kernighan<\/a> at Bell-Labs<\/a>.<\/p> Significant advancements introduced by C90<\/a> include the C-Standard-Library<\/a>, function prototyping to improve Type-Safety<\/a>, and support for wide characters. These features ensured greater Portability<\/a> across diverse Operating-Systems<\/a> and hardware architectures. Modern Compilers<\/a> like GCC<\/a> and Clang<\/a> continue to provide legacy support for this standard. For official documentation, visit the ISO Standards Page<\/a> and the ANSI Website<\/a>.<\/p>