What is the difference between backquote and backtick .

Really, i search on this issue . And it seems that are the same .

`

If so , Is it a synonyms ?

The two words can be used interchangeably. Which one is common depends on the specific programming language community. In particular, programmers in Lisp and Lisp-like languages (e.g. Scheme) tend to use the word backquote, because this is the term used in the Common Lisp specification (and earlier language documents); in Lisp, the use of the backquote character is a variation on the quote character (it allows "unquoting" within the expression), hence the parallel names.

In other language contexts, backtick seems to be more common, because the character is not doing a form of quoting (although MySQL's use is similar to quoting).