[nr2d]

Can a text message be sent to a non-Apple device or web site from an iPad? I'm trying to register my
iPad Air 2 on Facebook but iMessage won't let me send the message to Facebook.

I am using a cell enabled iPad on AT&T.

This is an effort to try to fix a session expired error when I try to log in to Facebook using the iOS 8 Facebook APP. The problem is on Facebook's side not with the iPad/iPhone or the Facebook APP.

[HankAZ]

Can a text message be sent to a non-Apple device or web site from an iPad? I'm trying to register my
iPad Air 2 on Facebook but iMessage won't let me send the message to Facebook.

No. iMessage is an Apple messaging system between Apple devices. You have to use SMS - or in the case of an iPad, you can get it done using the continuity/handoff function of iOS 8 and Yosemite.