1.Basically this means using this chip you can use DC motors and power supplies of up to 12 Volts
2.Thats some pretty big motors and the chip can supply a maximum current of 600mA per channel, the L293D chip is also what's known as a type of H-Bridge.
3.The H-Bridge is typically an electrical circuit that enables a voltage to be applied across a load in either direction to an output, e.g. motor.
4.2 connections for 5V 'hobby' servos connected to the Arduino's high-resolution dedicated timer - no jitter!
5.Can drive 4 DC motors or 2 stepper motors or 2 Servo.
6.Up to 4 bi-directional DC motors with individual 8-bit speed selection.
7.Up to 2 stepper motors (unipolar or bipolar) with single coil, double coil or interleaved stepping.
8.4 H-Bridges: per bridge provides 0.6A (1.2A peak current) with thermal protection, can run motors on 4.5V to 12V DC.
9.Pull down resistors keep motors disabled during power-up.
11.2 external terminal power interface, for seperate logic/motor supplies.