Put in by Google Analytics, _gid cookie stores information on how website visitors use a website, even though also building an analytics report of the web site's performance. Several of the facts that are gathered include the number of site visitors, their source, as well as webpages they visit anonymously. https://share.evernote.com/note/83defcab-8851-fa9f-479e-d8e8f1bab4df