Article I in the U.S. Constitution establishes the legislative branch, which is sole possessor of legislative power and the principal forum for deliberating and debating federal laws. The legislative branch is divided into two houses, the House of Representatives and the Senate, which share legislative power but also each have particular rights and responsibilities. Specifically, the House of Representatives has the sole authority to introduce spending and taxation bills, while the Senate has the sole authority confirm Presidential appointments and approve treaties.
The United States Constitution, What It Says, What It Means, A Hip Pocket Guide