One-Push: 

Used in conditions where AWB (Auto White balance) is unable to detect and use a white image to auto set the white balance.  Basically, you fill the frame with what you know to be a white object (even under colored lighting), this is saved as the camera's "white" reference and camera now auto-white-balances using the new reference "white" instead of it's internal reference.


ATW: Auto Tracking White Balance

ATW is a more dynamic version of AUTO white balance.  It detects when your ambient lighting shifts significantly (such as moving from indoors to outdoors) and dynamically changes the AWB for you.


Manual:

You Set the white balance options based off of Red and Blue gains.


Auto:

Automatically detects light in the room and selects the best white balance option for you. 


Indoor:

Preset settings for indoor camera use.


Outdoor:

Preset settings for outdoor camera use.