15|10 means 15 minutes with 10 seconds increment for every move played.
On average, It is a bit shorter than 30 minutes per side.
Most rapid players online plays 10|0 which is a pretty fast time control. Actually, for most people such time control is not optimal for improvement. For improvement, for most of the people, anything less than 15|10 is probably not optimal. Personally, I enjoy longer time controls the most.
What should you play? It depends. What is your goal? Improvement? The best thing you can do is to play longer time controls, because that will help you to think on your moves. In that case, after you play a game, stop and try to figure out what you did right and wrong in that game in order to get the most out of your games.
If you enjoy slower chess, try out 60|0 or 45|45 games. At 800-900 rating, you will still have plenty of opponents probably. Around 1 400 - 1 500 you can see a significant drop in people playing such games.
If you just want to have some more casual games and enjoy chess without caring about improvement, you should try out different time controls and see which one you enjoy best.
Chess clock time for beginner who wants to keep it moving but have time to think . . .
Thank you. That's helpful.
Time Controls - Everything You Wanted To Know...
https://www.chess.com/blog/RussBell/time-controls-everything-you-wanted-to-know
Play Longer Time Controls...
For many at the beginner-novice level, speed chess tends to be primarily an exercise in moving pieces around faster than your opponent while avoiding checkmate, in hopes that his/her clock runs out sooner than yours. And/or hoping to notice and exploit your opponent’s blunders while hoping they don't notice yours. The reason for this is that there is little time to think about what you should be doing.
It makes sense that taking more time to think about what you should be doing would promote improvement in your chess skills and results.
An effective way to improve your chess is therefore to play mostly longer time controls, including "daily" chess, so you have time to think about what you should be doing.
This is not to suggest that you should necessarily play exclusively slow or daily time controls, but they should be a significant percentage of your games, at least as much, if not more so than speed games which, while they may be fun, do almost nothing to promote an understanding of how to play the game well.
Here's what IM Jeremy Silman, well-known chess book author, has to say on the topic...
https://www.chess.com/article/view/longer-time-controls-are-more-instructive
And Dan Heisman, well-known chess teacher and chess book author…
https://web.archive.org/web/20140627052239/http:/www.chesscafe.com/text/heisman16.pdf
https://www.chess.com/blog/RussBell/dan-heisman-resources
and the experience of a FIDE Master...
https://www.chess.com/forum/view/general/how-blitz-and-bullet-rotted-my-brain-don-t-let-it-rot-yours
for some good stuff on general chess improvement, with a view toward learning what you should be doing, browse my blog.....
https://www.chess.com/blog/RussBell
As a beginner determined to improve sometimes I need to think awhile. Blitz/Bullet happens too fast to make it worthwhile for me. I have been playing Rapid 30 mins, but more and more I find myself running out of time and blundering in the final few minutes because of time pressure. I looked at longer Rapid options. I see 60 minutes, which seems a little long, and 15|10 and 45|45. Two questions: 1) Can someone explain to me what those latter options are? 2) What do most Rapid players play?