We can use a subordinating conjunction (dependent word) like because, although, as, until, unless, when to join two sentences together. Notice that in the above example we have the dependent word although at the beginning of the sentence. Because of this, the clause “Although Joe likes eggs” becomes a dependent clause, meaning that it cannot stand alone as a complete sentence. What we end up with, then, is one dependent clause and one independent clause (complete sentence). A comma is strong enough to join a dependent and independent clause together, so this comma use is acceptable and does not create a comma splice error.