The F# Language Specification gives an in-depth technical explanation of the F# language constructs and required compiler behavior. It discusses topics such as lexical analysis, grammar, types including type inference algorithm, expressions, patterns and other.

F# 2.0

F# 3.0

F# 3.1

F# 4.0

F# 4.1

F# 4.1, 4.5, 4.6, 4.7, 5.0