About git tags

tag the current commit

 git tag -a tagname -m "message"

delete the tag locally

 git tag -d tagname

to see about a tag, use 'git show tagname' or see it in bitbucket web's commit board.

tags need to be pushed to the server use 'push --tags'

 git push --tags

or

 git push origin master --tags

remember to use 'git fetch' to pull the update of tags

 git fetch --tags

use 'git checkout' to go back to some commit(tag), after that, use 'git checkout master' to come back~

 git checkout tagname