hosts

Hosts is a plural term used across several fields to describe an entity that provides a place, resources, or support for another, or one that harbors another organism. The precise meaning depends on the domain, but the common idea is a relationship in which one party enables or sustains another.

In computing and networking, a host is a device connected to a network that can offer or consume services. Typical hosts include computers, servers, smartphones, and virtual machines. Each host has a network address, such as an IP address, and often a hostname that maps to that address via the Domain Name System. Hosts participate in client–server interactions and may run services like web servers, mail servers, or file servers. In modern infrastructures, physical hosts may host multiple virtual machines or containers, and host management is a key part of network administration and cloud computing.

In biology and medicine, a host is an organism that harbors a parasite, pathogen, or symbiotic organism during part of its life cycle. Hosts can be classified as definitive, where the parasite reaches sexual maturity, or intermediate, where development occurs without maturation. Some ecosystems also describe reservoir hosts, which maintain a pathogen in nature and facilitate transmission to other species.

In everyday use, a host is a person who receives guests or audiences, or who organizes and leads an event, show, or broadcast. The term also appears in related phrases such as hosting a website or hosting services.