Standard Content is just an extension of content defined DVD-Video Version 1.1 especially for high-resolution video, high-quality audio, and some new functions. Standard Content consists of one VMG space and one or more VTS spaces, which are called "Standard VTS" or just "VTS".
Some highlights of these extensions are:
Standard Content contains EVOBs, which consist of video, audio, subpicture, and other data multiplexed together. Standard Content EVOBs contain button highlight and other information that is not used in Advanced Content.