Digital Communication is the electronic exchange of information.
We communicate digitally when we use cell phones, instant messaging (IM), text messaging, and e-mail. We also communicate digitally when we post a comment to a blog or update a wiki!
Social Networking is communicating online, in a virtual way. Many times people who are interested in a particular subject or topic communicate online using blogs, wikis, or online social networking sites such as Facebook or MySpace to "hang out" and chat. These sites and Web 2.0 applications bring about a lot of exciting opportunities, BUT it is important to be smart and savvy.