LME prices as opposed to "spot" prices

could someone briefly explain the difference and which prices "traders" observe ie do people take much notice of "spot prices" on kitco .com or the LME prices on Basemetals. com what would be the variance in prices ie a few cents in regards to zinc. i have googled it but am still confused. why have both markets etc, and which one is more important to monitor

thanx

Spot prices on kitcometals are only semi-accurate. The 'real' price to look at is the 3m futures.

eg. http://data.tradingcharts.com/futures/quotes/HG_.html

After the LME closes, Globex in the US takes over.