This is the GitLab 7.x specific tag. Use it in addition to the gitlab tag if your question is specific to GitLab 7.x — not just GitLab.
GitLab is open source software to collaborate on code. It can be considered as an open source self hosted github. You can checkout a GitLab demo.
Information
This tag is specific for the 7.x version of GitLab, which was released on the 22th June 2014. See the gitlab tag for general GitLab questions.