The Quarians are a nomadic species of humanoid aliens known for their skills with technology and synthetic intelligence. Since their homeworld Rannoch was conquered, the quarians live aboard the Migrant Fleet, a huge collection of starships that travel as a single fleet.
Approximately three hundred years ago the quarians created the geth, a species of rudimentary artificial intelligences, to serve as an efficient source of manual labor. However, when the geth gradually became sentient, the quarians became terrified of possible consequences and tried to destroy their creations. The latter won the resulting war and forced their creators into exile. Now the quarians wander the galaxy in a flotilla of salvaged ships, secondhand vessels, and recycled technology.
A great deal of quarians have found their way onto a Normandy. How this happens exactly is not generally known. Due to their famed engineering skills, it is entirely possible that an instant teleportation device has been constructed which connects the Flotilla directly to one or more Normandy(s).
The majority of ME Twitter Quarians are on their Pilgrimage and find that the best way to complete it is to spend time on a Normandy drinking coffee, eating dextro ramen, dextro pizza, crawling through vents, flirting with Tali'Zorah and occasionally fixing something. ME Twitter Quarians typically come from the Rayya or the Idenna.
Quarians are characterised by their love of dextro coffee, ramen, pizza, vents, Tali'Zorah and their dislike of Geth. Special issues of Fornax focusing on Quarians are often extremely popular, particularly the last few years since Tali'Zorah nar Rayya's "coming out into society" as a leading Quarian engineer. Many fanboys loyally purchase each issue as soon as it is released in a desperate attempt to relieve their loneliness.