As president, one of Barack Obama's most important tasks is making appointments to the federal courts.
The Senate has a role to play too. They are to "advise and consent." If a judicial appointee is deemed unqualified, a majority of the Senate can vote him or her down.
Obama nominated Sonia Sotomayor to the U.S. Supreme Court, and the Senate performed its role. Sotomayor, who had a long record of judicial service, now sits on the nation's top bench.