What's difference between "Import mail and contacts:" and "Check mail using POP3:"?

[Bin]

Of course I know the previous one can also fetch the contacts, but
what's the essential difference between these 2 ones? I can't tell
the difference.

Is the first one real-time? I know if you sent pop3 for some other
email in Gmail, it checks the new email every 1 hour. will the "import
mail and contacts" option check the email real-time?

anyone knows?

thanks
-Bin

[Ryan Morehart]

The import feature is meant to help the transition from an old
account, so it helps you get all your old messages over to Gmail but
then only keeps checking for new ones for 30 days. If you want your
Gmail account to permanently be checking an account, you'll want to
use the fetching over POP3 feature.

As a side note, the POP fetcher will actually check more often if the
account is busy, up to a maximum of around 15 minutes.

Ryan

[Bin Sun]

Sounds reasonable, thank you very much!