plasma is a gas held between glass plates and electric current is transferred through it to create a picture.
LCD is a 'pool' Liquid Crystals which also have current being passed through to arrange the crystals to make a picture.
average life span for a plasma is 6-8 years ie it fades as the gas disapates
average life span of LCD is almost lifelong, lcd screens start from 3inch up to 50"
plasmas start at 40" and go to 120"
the average resolutiuon of a 42" plasma screen is 800x600 and the resolution of a 42" LCD is 1280x1024 on average, the higher the res the more pixels therefore better clarity.
LCD is the best quality out of the two BUT the price difference is alot, HI- Definition is avaliable in both but the LCD wins everytime, plasma is getting better but still has a pixelated look to it close up unlike LCD.
There are alot more good/bad points about each type but those are the main ones.
