MPG is a video format standardized by the Moving Picture Experts Group (MPEG), typically incorporates MPEG-1 or MPEG-2 audio and video compression.
This file format was designed specifically for use with Video-CD and CD-i media. The most common implementations of the MPEG-1 standard provide a video resolution of 352x240 at 30 frames per second (fps). When you use this standard, you receive a video that is slightly lower-quality than typical VCR videos.
Today, higher quality video format like AVI/MKV (with xvid, MPEG-4 codec) is a better choice.