Welcome to this Friendica node!
Friendica is a decentral social network platform everybody can use to setup their own social networking node. It interacts with many other FLOSS microblogging and social networking platforms as well as some walled gardens.
Every network that speaks either the DFRN2, OStatus or diaspora* protocol. Currently this list includes: diaspora*, friendica, ganggo, GNU social, Hubzilla, Mastodon, Pleroma, postActivi and Socialhome.
No, not at all! You need a LAMP server, most shared hosting services that offer MySQL, PHP and the ability to run cron jobs will do just fine. If you have your own (virtual) server, for a small Friendica server something like a Raspberry2B is sufficenent from the specs.