Fortran was originally created by a team lead by John Backus at IBM in 1957. Originally, the name was in all capital letters, but current usage is only requiring that the first letter be capitalized.
The name Fortran stands for FORmula TRANslator. It was originally aimed at scientific calculation and had limited support for working with characters. Until the C language became popular, it was one of the few high level languages with a high level of portability between different computer systems.
Several websites indicate that the work on Fortran was started in 1954 and released commercially in 1957. 20 September 1954 may have been the day that a small Fortran program was first successfully compiled.
There have been several versions of Fortran. Fortran I, II and III are considered obsolete. The oldest Fortran versions which are considered of much use today were Fortran IV, and Fortran 66, which, as the name implies, was released in 1966. All later versions of Fortran are numbered after the year the standard was released. The versions of Fortran most commonly remaining in use are Fortran 77, Fortran 90, and Fortran 95.
In Fortran II, IF statements had the form: IF (numericExpression) lineNumberIfNegative, lineNumberIfZero, lineNumberIfPositive. It also had an odd type of string literal, called Hollerith literals (after the inventor of the keypunch and IBM). Where today one might code 'hello', Fortran II used 5Hhello. However, there was no string variable type.
Fortran IV added the IF/THEN concept, the concept of logical expressions, with operators .AND., .OR., .EQ., .NE., et cetera. Complex numbers as a basic type were also added.
Fortran 77 added strings as a distinct type.
Fortran 90 added various sorts of threading, and direct array processing.
Although Fortran became a standardized language early, many companies had their own extensions to it. Strangely, IBM and DEC had virtually the same set of extensions.