git glob pattern in .gitignore and git command

To ignore all .js file under a directory `lib', I can use "lib/**/js" to match them. But when using git command such as "git add", using "git add lib/\*.js" is sufficient. Why is this difference in glob mode?

I have heard that there are many different glob mode out there (e.g., bash has many different glob mode). So, which classes of glob mode does these two belong to? Do they have a name?

Yubin