You can use some but not all. Like spaces, inserting non-alphanumeric characters into a file name could cause problems for browsers, servers, or the user.

Avoid commas, periods (except when preceding the extension), as well as: <, >, (, ), {, }, [, ], |, \, ^, ~, # (if it’s not a fragment identifier), and % (if it is by itself). If these must be used within a URL, they should be encoded.

Safe characters to use in files not produced by a database include the underscore and hyphen. There are some reserved characters that should not be used: ;, /, ?, :, @, =, and &. If you link to a URL with an ampersand (&) replace it with & (or &) so it will validate in the future—its required in XHTML.