What is Twitter?

So, the NCAA doesn't allow Twitter comments about recruits by current players or anyone associated with a Uni.  They, supposedly, think it is 'broadcasting', as texting the recruit is OK.

Then, the AD of a University Tweets to an athlete at another school, and everyone is up in arms because it was a direct message.  Some say it would have been OK, if he had just commented on it and not made it sent to him "personally".

Twitter is confusing.