Host for GlassWire specifically means a network host which is a computer or device attached to a network and assigned a network address such as an IP address.
The term host is often used interchangeably with the term server but they are not always the same. All servers are hosts but not all hosts are servers. Servers are network hosts that accept connections from other network hosts which are usually called clients in the client-server model.
The rest of this topic provides more information on the origin of the term and how it is used in subtly different ways within computing.
The meaning came from hosts as people
Host is a word transferred almost directly from its normal context in human relationships and applied to computer in their relationship to other computers.
A human host provides hospitality to other people:
a person who receives or entertains other people as guests.
Likewise, a computer host provides services to other computers:
a computer that receives or services other computers as guests.
Host computers have many different contexts
Host is used in many computing contexts, all with a similar meaning but some subtle differences
As we've said already, a network host is a computer or device attached to a network and assigned a network address.
There is one feature of network hosts that doesn't apply to other meanings. A network host doesn't have to provide services to any other computer or device to be called a host. But it does have to have an address on a network.
Any hubs and switches which don't have network addresses are not hosts. They are usually invisible to us network users because they are part of the infrastructure (including cables and jack points) that the network runs on.
A host is often larger and more powerful than the computers it services. This was particularly true when mainframe computing dominated before personal computing took over:
A mainframe host is a more powerful computer servicing less powerful computers
A large centralised computer system was called a mainframe and attached to it were relatively dumb computer terminals. Now a mainframe is more likely to mean a large server that provides computational processing to attached computers called thin clients.
A web host is primarily a computer that hosts web sites and web services on the world-wide web (www).
The term is also applied to the company that owns or runs the service. So if I say that I am looking for a web host then I can mean that I am looking for either or both of a web host server and a company that provides a web hosting service.
A virtual host appears to be one physical host even though it is sharing physical computers.
A virtual host can be sharing one physical server or be shared across a group (cluster) of servers.
The main use of virtual host is for web hosting where one web server provides several virtual hosts to service different IP addresses and/or domain names. Virtual hosting and virtual servers is how most of us get our web hosting.
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