--> House of Commons is similar to our Dutch 'Tweede kamer'. Members are
publicly elected.
--> House of Lords is similar to our Dutch 'Eerste kamer'. Members inherit
seats of are appointed by the Crown.
The business of Parliament takes place in these two houses. Their work is similar: making laws (legislation), checking the work of the government , and debating current issues. Generally, the decisions made in one House have to be approved by the other. This way they keep each other in check.
In this way the two-chamber system acts as a check and balance for both Houses.