Subordinate clauses are dependent upon main clauses or other dependent clauses. They can't stand on their own. Frequently they begin with certain words (subordinating conjunctions, relative pronouns or interrogative words) that connect them to the independent clause.

"obwohl" is a conjunction that heads a concessive clause. "obwohl" (although) clauses express something contradictory or surprising in contrast to the statement made by the main clause.

Example:
Ich trinke ein Bier, obwohl ich lieber Wein mag.
(= Ich mag lieber Wein. Trotzdem trinke ich ein Bier, z. B. weil es hier in der Kneipe keinen guten Wein gibt.)

Subordinate clauses with the "obwohl" conjunction are always separated from the independent clause by a comma and the conjugated verb always comes at the end of the subordinate clause.

Examples:
Das Lieblingsbier der Deutschen ist das Pils, obwohl ich es überhaupt nicht mag.