Contracts of employment is a type of contract utilized under various United Kingdom labor laws. The contract takes place between the employee and employer. Such employment contracts originated prior to the 20th Century and were based on master-servant laws. Today, the contracts of employment define a relationship of social subordination and economic freedom. Technically speaking, a contract of employment is often called a contract of service. Most contracts focus on wages, holiday pay, pension schemes, stop options, health insurance benefits, fringe benefits, and required work hours. Some employers might also opt to include a non-compete or non-disclosure clause in the employment contract. This helps the employer protect vital trade secrets from being revealed once an employee departs from the company. U.K. law dictates employment contracts have assumed, essential, and unspoken terms, all of which are implied. Furthermore, the law states that explicit terms can also be included in the contract.