Elizabeth "Liz" Lemon is the fictional protagonist of the American situation comedy 30 Rock. She is portrayed by Tina Fey, who is also the creator of the series and its show runner.
Like Fey, who was head writer of Saturday Night Live (SNL) from 1999 to 2006, the character is head writer for a fictional SNL-esque show, The Girlie Show.
For this reason, Liz Lemon is widely seen by critics as a fictionalized version of Fey herself, which Fey herself has confirmed as being her intention.
Jack: Avery and I want the baby's middle name to be Elizabeth, after you.
Liz: Oh Jack, that's so gay balls.
Pete: Oh my god! Wha... what are you wearing?!
Frank: You're making me gay.
Liz: It's a joke, obviously. I'm wearing this as a joke. Bunch of comedy writers don't know a joke, jeez. [goes to her office]
Frank: I just threw up in my mouth.
Liz: I said it's a joke!