TFT stands for thin film transistor is not really different from LCD and TFT, comes from the family of the LCD technology. LCD is a thin, flat display device made up of any number of color or monochrome pixels arrayed in front of a light source or reflector and an LED display is a flat panel display, which uses light-emitting diodes as a video display. nowadays various big manufacturing companies like lg, samsung, sony, panasonic and more are going to offer lot more varieties in lcd and led.

The only difference is the backlighting. Standard LCD monitors use a fluorescent light to backlight the LCD screen. LED LCDs use white LEDs to backlight the LCD screen. The result is a monitor that lasts longer, consumes less power and is thinner

LED stands for light-emitting diode. It's used as backlight for newer LCD monitors and it's quite popular with laptops because of its energy efficient design. Most LCD monitors use CCFL for illumination. CCFL stands for cold cathode fluorescent lamp. For gaming, you'll want an LED-backlit LCD monitor. It offers better (and more even) illumination.
LCD uses liquid crystals. they don't generate any light of their own so they need back lighting which "washes out" the colors creating a poor contrast ration. an LED each pixel is an individual LED light, because of this it requires no backlighting and the contrast is near perfect, also it would be significantly thinner and require far less energy to run. The only downside to LED TVs is a relatively short life span and high cost.

Source: google search

Clarity difference

Led iz best but 3d tv r overtaking