Internet Service Provider. A company that provides you with Internet access, usually through a dial-up, DSL, or broadband connection. ISPs can also offer related services like email accounts, web hosting, domain name registration, and even data communications and telephone services (see VoIP).
An Internet service provider (ISP) is an organisation that provides services for accessing, using, or participating in the Internet. Internet service providers can be organised in various forms, such as commercial, community-owned, non-profit, or otherwise privately owned.