Note: Screens based on either of these technologies are non-interchangeable. This is because the laptop is designed for only one type of backlight. So a laptop with a CCFL panel cannot use a LED panel and vice versa.
In order to ensure you are purchasing the best screen to fit your needs, here are three things you can do:
LED, LCD, and CCFL - what do these mean?
Liquid crystal displays (LCDs) do not produce any light by themselves, so they need a source of light to illuminate an image and make it visible. In laptop LCDs this illumination is made possible with a backlight, so called because it is positioned on the back or side of the panel.
Cold Cathode Fluorescent Lamp (CCFL)
CCFL's are an older technology, and for the moment are the most widely used backlights in laptops LCDs. They consist of a fluorescent tube connected to a voltage inverter board which provides power to the backlight. Sometimes the backlight contains 2 tubes along with 2 pairs of inverters; these are called "Dual Backlights" or 2-CCFL.
Light-Emitting Diode (LED)
LED's are a newer technology and use a matrix or a strip of LED's instead of a tube. Most LED based backlights do not need inverters. LED backlights are already used in most mobile devices like phones and GPS devices. LED use in laptop screens has recently become popular due to advantages in size, power consumption, etc.
Differences in CCFL and LED Backlight Technologies