Ignore files from Git

I've created my hello project and want to put it into Git.  All the online tutorials I read start with the same commands when creating a project:

git init
git add .

However, doing this will result in adding files and directories I do not want to commit. Fortunately, you can setup exclusions with git. There are several ways to do exclusions.  I used the method of adding a global exclusion file:

git config --global core.excludesfile ~/.global_ignore

This command sets up a global exclude file named ".global_ignore". So, any project I setup with git will use the exclusions I define in that file.

Here is what is in my .global_ignore file:

#generic files to ignore
*.DS_Store

#Java files
*.class
*.jar
*.war
*.ear

#Maven
target/

#IntelliJ
*.iml
*.idea

Now, when the "git add ." command is run, only my source files are marked for addition.

# On branch master
#
# Initial commit
#
# Changes to be committed:
#   (use "git rm --cached ..." to unstage)
#
# new file:   README
# new file:   pom.xml
# new file:   src/main/java/foo/bar/HelloWorld.java
# new file:   src/main/webapp/WEB-INF/web.xml
# new file:   src/main/webapp/index.jsp

References:
http://man.cx/gitignore - MAN page for gitignore
https://github.com/github/gitignore - A collection of useful .gitignore templates
http://help.github.com/ignore-files/ - GitHub's help page for gitignore