What is a stuck pixel?
A stuck pixel is a bright dot of colour most noticeable when the rest of the screen is black. Stuck pixels are fairly common on high resolution LCD screens. Stuck pixels sometimes start working again with time unless they appear black on a white background, these are known as dead pixels.
What is screen burn-in?
Dark patches on a plasma screen are the result of screen burn-in. Burn-in occurs on plasma screens if an area of the screen does not change for a long period of time. For TV input, channel logos often burn into the screen. This can also occur on LCD screens and is more correctly referred to as image persistence.