Sometimes you may want maintain versions of a git repository on machines that have no network connection. Bundles allow you to package git objects and references in a repository on one machine and import those into a repository on another.

git tag 2016_07_24
git bundle create changes_between_tags.bundle [some_previous_tag]..2016_07_24

Somehow transfer the changes_between_tags.bundle file to the remote machine; e.g., via thumb drive. Once you have it there:

git bundle verify changes_between_tags.bundle  # make sure bundle arrived intact
git checkout [some branch]       # in the repo on the remote machine
git bundle list-heads changes_between_tags.bundle # list the references in the bundle
git pull changes_between_tags.bundle [reference from the bundle, e.g. last field from the previous output]

The reverse is also possible. Once you've made changes on the remote repository you can bundle up the deltas; put the changes on, e.g., a thumb drive, and merge them back into the local repository so the two can stay in sync without requiring direct git, ssh, rsync, or http protocol access between the machines.

Remarks

The key to making this work is to begin by cloning a bundle that starts from the beginning of the repo history:

git bundle create initial.bundle master
 git tag -f some_previous_tag master  # so the whole repo does not have to go each time

getting that initial bundle to the remote machine; and

git clone -b master initial.bundle remote_repo_name