A background check is a process a person or company uses to verify that an individual is who they claim to be, and this provides an opportunity to check and confirm the validity of someone's criminal record, education, employment history, and other activities from their past. The frequency, purpose, and legitimacy of background checks vary among countries, industries, and individuals. An employment background check typically takes place when someone applies for a job, but it can also happen at any time the employer deems necessary. A variety of methods are used to complete these checks including comprehensive database search and personal references. Purposes Employment screening Background checks are often requested by employers on job candidates for employment screening, especially on candidates seeking a position that requires high security or a position of trust, such as in a school, courthouse, hospital, financial institution, airport, and government. They can also be requested when purchasing a firearm (from a legal authorization). These checks are traditionally administered by a government agency for a nominal fee, but they can also be administered by private companies. Results of a background check typically include past employment verification, credit history, and criminal history. The objective of background checks is to ensure the safety and security of the employees in the organization. These checks are often used by employers as a means of judging a job candidate's past mistakes, character, and fitness, and to identify potential hiring risks for safety and security reasons. Background checks are also used to thoroughly investigate potential government employees in order to be given a security clearance. However, these checks can sometimes be used for illegal purposes, such as unlawful discrimination (or employment discrimination), identity theft, and violation of privacy. Checks are frequently conducted to confirm information found on an employment application or résumé/curriculum vitae. One study showed that half of all reference checks done on prospective employees differed between what the job applicant provided and what the source reported. They are also conducted as a way to further differentiate potential employees and pick the one the employer feels is best suited for the position. Employers have an obligation to make sure their work environment is safe for all employees and helps prevent other employment problems in the workplace. Firearms purchases In the United States, the Brady Bill requires criminal checks for those wishing to purchase handguns from licensed firearms dealers. Restricted firearms (like