Answer:
A rip current is when a tide cannot escape directly, maybe because it is trapped in front of a reef, sandbank or something. When the water finds an exit point, it all rushes out at top speed, therefore sending whatever is in the water at the time out to see.
Meanwhile, a longshore current is when something ( the wind ) is angling the water's course as it heads towards the shore, therefore creating a current running parallel to the beach. Longshore.