What is DVD high compatiability mode?

I was just wondering, because it says in Nero that “at least one Gb will be written”, does that mean I can only burn 1 Gb less of data on each DVD? Sorry if this is kind of obvious, I’m really new at this.

Thanks =)

I believe some drives (mostly older?) have issues reading DVDs which contain less then 1GB of data, so if you burn less then 1GB of data it will pad the disc with additional data to bring up up to 1GB. If your project already has more then 1GB, that option will not do anything.

–> http://www.burnersoft.com/dvdcd/help/index.html?faq.htm

What is “DVD High Compatibility Mode”?
The DVD High Compatibility Mode is used to aid compatibility with certain DVD drives and players (by padding the disc with dummy data to a minimum of 1GB), but it will greatly increase the burning time. You should enable this option only if you encountered incompatibility issues with some DVD drives/players.

Ah ok I get it now. Thanks for the response =)