Can someone explain adb please.

[Genious#AC]

Im completely new to android, an I keep reading about people performing hacks or mods using adb push. What exactly is it?

 

[krelvinaz]

adb is one of the tools used in the Android SDK.

Android SDK | Android Developers

Normally, you would download and install the SDK so that you can use the tools and develop.

 

[Jerry Hildenbrand]

Android Debug Bridge

Like krelvinaz says, it's part of the Android SDK. It's a program that lets you type commands into a command line (windows) or terminal (Linux, Mac) on your computer, and have the commands be run on the phone.