Posted 10 July 2012 - 12:26 AM
As Fede-Lasse remarked in the first post, Delta-Time is a programming trick developed to get around lag.
How it derived it's name actually comes from physics; the change in something is designated by the Greek Letter Delta, so the change in time is Delta-Time.
While it can be useful in single player games to prevent glitches do to lag or slow rendering, it can also cause some interesting trouble when the frame rate suddenly increases.
Normally, a game runs at 30fps, but the background programming in a DLL or other sub program of the game could be running much faster or slower depending on the type of code being run.
I took college courses on game and web design (Was one of the last to grab a slot for it being available at the Associate's level, as it is now only available at the Bachelor's level.) Delta-Time was actually used in the C++ class as an example of what basic coding could be used for. (Was combine in a DO WHILE loop with cout to to show how many times in 5 seconds the loop would run.)