why windbg command start with . or !

Question

Is there any difference between . and ! ?

Answer 1

There are different kinds of commands in WinDbg.

Regular commands, e.g. kb apply to the debugging session. E.g. show stack dump etc.

Meta commands are prefixed with a dot, e.g. .load. Meta commands apply to the debugger itself. E.g. load extensions, show help and so forth.

Extension commands are prefixed with an exclamation mark, e.g. !analyze and !dumpheap are defined in debugger extensions (DLLs that provide additional functionality).

Answer 2

Meta command prefixed with dot(.) are designed to configure or query debugger

Extension commands are prefixed with an exclamation mark(!) are used to invoke windbg plugin