Complex sentence: Similar to VCDs, SVCDs are authored (or "burned") using the CD-ROM XA Mode 2, Form 2 format, allowing roughly 800 megabytes of data to be stored on one 80 minute CD (versus 700 megabytes when using mode 1).
Split into simpler sentences: Similar to VCDs, SVCDs are authored (or "burned") using the CD-ROM XA format. This allows roughly 800 megabytes of data to be stored on one 80 minute CD (versus 700 megabytes when using Mode 1).