Run-on Sentence

A run-on sentence is a "fused sentence" that joins two or more complete sentences without using punctuation.

Example: Michaela loves to draw horses she is a talented artist.

It becomes a comma splice when these sentences are only connected by a comma.

Example: Michaela loves to draw, she is a talented artist.

(source=http://ace.acadiau.ca/english/grammar/runon.html )