It's really helpful for people not used to this world or time. Basically these are virtual platforms that help with content creation and facilitates the interaction of ideas, interests, and opinions without having to be right in front of other people. Takes the anxiety out of meeting new people and helps you connect with likeminded people. Twitter's another big one and so is Facebook and Tag!
You're in luck - you're not going to find any shortage here. My husband's a co-commander over with the Defense Teams you've heard about, so I'm sure he or Sara Lance will be in touch with you soon. You can always go down to the DOA if you're impatient though.