I’m looking at DVD writers and find that some support DVD+R and DVD+RW while others support DVD-R and DVD-RW, and some support both + and - formats.
Obviously, I want one that supports both, but what is the difference? Which format do home DVD players use?
Also, do I have to buy different blank discs if I am recording in + format and - format?
I’m so confused. 
On “The Screen Savers” TV show they said that any home DVD player built in the last 3 years or so will probably ready either +R or -R. Their main point was on the fact that the major players (Sony, HP and somes other I can’t remember, maybe Philips?) are pushing the +R standard so it’s more likely the one to survive long term.
DVD-R is slightly more compatible with older DVD players, and faster to record, than DVD+R.
On the other hand, DVD+RW is slightly more compatible and faster to record than DVD-RW.
There are some other technical differences, but from the user’s POV they don’t really matter. Buy a drive that will write both formats; you’ll be happy and future-proof.
If you mean which format are store-bought DVDs in, then none of the above. They are pressed specially. If they were burnt like consumer writable CDs and DVDs, it’d take much longer for each disc and the discs themselves wouldn’t last as long.
“Which format do home DVD players use?”
They probably use Authoring disks/recording, which is neither of them.
What a player can read depends on the player itself & I have to know which one you’re talking about.
I have the Sony DRU-500AX, which does both +/-. I use DVD-R for my movies (since that’s all my DVD player will play), and DVD+RW because it formats faster than -RW.
FTR, DVD-R is compatible on about 88% of all DVD players, and DVD+R is compatible with about 84% of them…although there are some that play +R and not -R…just check your player.
I didn’t want to wait for the format wars to wage, so I just skipped them, and I love my drive!
Whatever happened to DVD-RAM? Has it fallen by the wayside?
MS appears to have chosen to support dvd+r instead of dvd-r…nuts.
“Whatever happened to DVD-RAM?”
Nope, it’s still around, I use that too. Formatting a disk takes about 10 seconds, Vs. a dvdrw which takes around a half hour. DVD-RAM are rated 100,000 rewrites. Plus you can use double sided ones. One of my dvd recorders that takes the place of my vcr, does DVD-RAM & dvd-r …which is very handy.