Email account sync question

I know this is pretty basic, but I will ask anyway.
What's the 'Sync Interval' settings in email accounts?
For example, my Gmail account I set the sync Interval to 1 hour. But I still receive my mails immediately.
For Yahoo, I set it to2 hours. The mail is yet to come in.
The Hotmail account does not have a sync Interval setting option, and the email comes in immediately as well.

So what exactly is the difference between these accounts and what's the relevance of Sync Interval?

Also, I don't see a way how to set the sync or update Interval for FB, Twitter etc.. anymore. Is it not possible with BB10?



Posted via CB10

Sync interval is for imap based accounts where Hotmail is active sync.

Twitter etc pushes their notifications. No need to pull.

The sync interval also determines how often the read/unread status, changes in calendar & contacts are synced between device and the server.