The domain name .com is a top-level domain (TLD) in the Domain Name System (DNS) of the Internet. Added at the beginning of 1985, its name is derived from the word commercial, indicating its original intended purpose for domains registered by commercial organizations. Later, the domain opened for general purposes.

The domain was originally administered by the United States Department of Defense, but is today operated by Verisign, and remains under ultimate jurisdiction of U.S. law. Additionally, as the Internet was invented in the United States, most American businesses and enterprises have used the .com domain instead of a more U.S.-specific .us. Verisign registrations in the .com domain are processed via registrars accredited by ICANN. The registry accepts internationalized domain names.

The domain was one of the original top-level domains (TLDs) on the Internet when the Domain Name System was implemented in January 1985, the others being edu, gov, mil, net, org, and int. It has grown into the largest top-level domain, and has lent its name to an era in the late 1990s, the dot-com bubble, during which excessive speculation in Internet-related companies in a period of rapid growth in the use and adoption of the Internet led to a stock market bubble and crash.