Socket

"Socket" refers to a functionality in an item that will allow this item to be imbued with a magical gem. The mechanic in the game is basically allowing the player a limited control of what powers a weapon will grant him. These are usually associated with the main attributes.

Item Sockets

There are item sockets in Diablo III. Runewords are not returning, but magical and rare and unique (and other yet-unannounced item types?) will have sockets.

Not much is yet known about what can be put into sockets; gems of various types have been seen in the gameplay movies and in the BlizzCon 2008 demos, but their bonus properties are unknown. No jewels have been seen, and runes in Diablo III are for socketing into skills, not items. There may be (and probably are) other things to put into item sockets, but no info has been released about them.

Official Comments

Bashiok commented briefly on item sockets in February, 2009.[1]

We haven't released any information on our site, but it was possible to collect socketed items as well as gems in the BlizzCon demo... The gem stats at this point are more or less just the basics yanked from Diablo II to get the system running and have something to play around with.