Depends on the qualities you ask for in a friend/best friend. If mutual support features high, probably not. It's very easy to pretend agreement with someone on-line and particularly social media but they remove spontaneity from interactions which can be so important to some because it's people's immediate reactions that tell you so much about them.

However, I confess having not "made friends" on line for a decade and a half so things may have changed. I wouldn't have called friends I did meet as potential real friends. Just non-hostiles. You can't pop into the café, the pub, go shopping with them, visit them in their homes on a regular basis and stuff.
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