How to set GIT to ignore a few files - like properties or config files

From time to time there are files you don’t want git to track. There are a few methods of telling git what files to ignore.

Method One:

1.      Create a .gitignore file in your git repository home.

2.      Create rules inside the .gitignore file.

Examples:

# To ignore a ‘build’ folder

build/

# To ignore all ‘.class’ files

*.class

            We can use this method to ignore the folder/files that are specific to project (common to all users).
It can be pushed to central repository, so that all users can use the same .gitignore file.
Note: This method can not be used to ignore the files that are already tracked by GIT.

Method Two:

1. Create rules inside .git/info/exclude file.

Examples:

# To ignore a ‘.project’ and ‘.classpath’ files

.project

.classpath

This method can be used to ignore locally-generated files that you don’t expect other users to generate, like files created by your editor.

These rules can not be committed with the repository, so they are not shared with others.
Note: This method can not be used to ignore the files that are already tracked by GIT.

Method Three:

1.      Use --assume-unchanged.
                    git update-index --assume-unchanged <filename>

Example:

      # To ignore build.xml, run this command.

                        git update-index --assume-unchanged build.xml
Note: We can use this method to ignore the files that are already tracked. To track the file again, 
execute "git update-index --no-assume-unchanged <filename>". These commands do not affect remote repository.