Sync iPhone messages with Mac?

I want to know if there's a way to text people from my mac without using a new number. I'm using an iMac with the latest software.

There's a Message app on the Dock. You can use it to send iMessages.

Hmm?

One of the more interesting features of OS X Mountain Lion is the ability to synchronize messages between iMessage on your iPhone and Messages on your Mac. This means you can start a conversation on your Mac and continue it on your iPhone.

Set up for this feature is pretty simple. First, you need to enable a few things on both your iPhone and your Mac. Here's what you need to do.