The Glossary of Internet Frases (the G.I.F)

Welcome to the G.I.F, our glossary of terms for readers who aren't online all the time! If you're reading an article and come across a link styled like this, it'll lead you directly to the corresponding definition on this page, which are listed in alphabetical order below.

And for the record: This one's pronounced with a hard G. It's not a "jossary".