The political parties have the responsibility of making nominations for public office. For appointed positions within the US federal government the president and the executive branch nominate appointees, who must then be approved by congress. This includes federal judges, US attorneys and the heads of the different departments, bureaus and agencies. However, people can be nominated by members of their respective parties. In some cases, people nominate themselves or offer themselves up as candidates. Hence, the political parties nominate people to run for public office positions. The various nominees from different parties are the ones presented as candidates to be voted for.