Railway rule books developed alongside the railways whose activities they governed.
The earliest railways were open access affairs and the rules were largely there to promote good behaviour. As railway companies developed into operators as well as carriers the needs changed and rules came to promote safe methods of work.
When railways began to interwork the need for standardization became rapidly apparent and standard codes of rules were developed.
In recent years rule books have been shown to be wanting and new ideas have been developed more closely related to job function. This was found unnecessarily complicated and in 2003 a further approach was adopted, using 'plain English'.
The development of railways byelaws and miscellaneous instructions is also covered, together with various standard sets of regulations.