The C89<\/a> standard, also known as ANSI C<\/a>, represents the first formal standardization of the C Programming Language<\/a>. In 1983, the ANSI<\/a> (American National Standards Institute) formed a committee, X3J11, to establish a standard definition of C to improve portability and maintainability across different systems.<\/p> The standard was officially ratified in 1989 and is frequently referred to as C89<\/a>. Shortly thereafter, in 1990, the ISO<\/a> adopted the same standard with minor formatting changes, resulting in C90<\/a>. These two terms, C89<\/a> and C90<\/a>, describe essentially the same language specification.<\/p> Prior to this standardization, the language was largely defined by the book written by Brian Kernighan<\/a> and Dennis Ritchie<\/a>, often called K&R C<\/a>. The C89<\/a> standard introduced several key features, including function prototypes, the Modern Compilers<\/a> like GCC and Clang still support C89<\/a> compatibility modes, as many legacy systems and embedded applications continue to rely on this foundational standard. It was eventually succeeded by C99<\/a> and later C11<\/a>.<\/p> For further reading, consult the Official ANSI Website<\/a> or the Wikipedia entry on ANSI C<\/a>.<\/p>const<\/code> and volatile<\/code> qualifiers, and a formalized Standard Library<\/a>.<\/p>