Originally Posted by LarryJ

I fly B737s and have never heard of a lot of the things that you guys are talking about. LOL

Speeds used by the pilots on takeoff are:

V1 - Takeoff Decision Speed
Vr - Rotation Speed
V2 - Takeoff Safety Speed

Flaps are retracted in increments when reaching the minimum maneuvering speed for the current flap selection and accelerating.

A low-speed call-out is made to cross check airspeed indications and define the beginning of the high-speed reject regime. United uses 100kts, some airlines use 80kts.