Full form of LCD is Liquid Crystal Display.

Liquid Crystal is the material used to create each pixel on the screen. The material has a special property - it can 'polarise' light depending on the electrical charge across it. 

This feature allows the pixel to be created. Each tiny cell of liquid crystal is a pixel.

It is also known as TFT. TFT stands for Thin Film Transistor. TFT is the device within each pixel that sets the charge. 

And so sometimes they are called "Liquid Crystal Display" referring to the material they use or they are called "TFT Displays" referring to the tiny transistors that make them work. 

TFT is a variant of LCD technology. LCDs use much less power than a normal monitor.