All of these click-in descriptions contain spoilers, especially the bios of Marrow, Barrow, Lawrence, and Gabriel. If you're just looking for a quick, spoiler-free reference, use the notes next to each name.
ARROWs:
Acorn - predecessor to Gabriel
Barrow - helps run the Complex, gruff and anal retentive, mistreats Gabriel, has an unusual relationship with his brother, Marrow
Cabra - operator who doesn't get along with her twin, Hack
Callan - of a different ethnicity than her half, Miyamoto
Duet - seven-year-old brat
Duncan - likes to party, friendly
Gabriel - doesn't talk, except to Lawrence
Hack - operator who doesn't get along with her twin, Cabra
Idaho - friendly, likes physical labor
Lawrence - computer nerd, Gabriel's friend
Liet - seven-year-old brat
Marrow - kind and anxious, helps to run the Complex, very kind to Lawrence and Gabriel
Matt - fourty-year-old who acts like he's five
Miyamoto - of a different ethnicity than her half, Callan
Orange - predecessor to Lawrence
Rob - fourty-year-old who acts like he's five
Elizabeth - Marrow's primary, taught them to speak
Randy - Barrow's primary, taught them to drink
Mick - Engineer
Takahashi - In charge of their design