What does Standard message and data rates may apply means?

[MJNE]

Because put my cell phone number on my Facebook and Twitter.
But im scared that they might charged me.

P.S
Im unlimited text.

HELP ME!

[Lance]

This is usually used by third party services that are not part of your mobile plan.

For example, if you subscribe to receive a joke-of-the-day to your cell phone. They don't know what your mobile plan is, so they have to say that you could be charged your standard rates.

So if your are on unlimited text then if you subscribe to a service (horoscopes, jokes, etc.) then your plan provider most likely won't be billing you extra - but if there are downloads, a datarate charge may apply.

Check your plan's details or phone your provider to confirm.