In computer networking, a workgroup is a collection of computers on a local area network (LAN) that share common resources and responsibilities. The term is most commonly associated with Microsoft Windows workgroups but also applies to other environments.

Windows workgroups can be found in homes, schools and small businesses. However, while all three are similar, they don't function in the exact same way as domains and HomeGroups.

Microsoft Windows workgroups organize PCs as peer-to-peer local networks that facilitate easier sharing of files, internet access, printers and other local network resources.

Each computer that's a member of the group can access the same resources being shared by the others, and in turn, can share its own resources if configured to do so.

Joining a workgroup requires all participants to use a matching name. All Windows 10 computers are automatically assigned to a default group named WORKGROUP(or MSHOME in Windows XP). 

To access shared resources on other PCs within its group, a user must know the name of the workgroup that computer belongs to plus the username and password of an account on the remote computer.

Windows workgroups can contain many computers but work best with 15 or less. As the number of computers increases, a workgroup LAN eventually becomes very difficult to administer and should be re-organized into multiple networks or set up as a client-server network.

Windows domains support client-server local networks. A specially configured computer called the Domain Controller running a Windows Server operating system serves as a central server for all clients.

WINDOWS DOMAINS

Windows domains can handle many more computers than workgroups due to the ability to maintain centralized resource sharing and access control. A client PC can belong only to a workgroup or to a Windows domain but not both. Assigning a computer to the domain automatically removes it from the workgroup.

Corporate domains also typically include switches that network devices are plugged into in order to connect to the larger company domain.

MICROSOFT HOMEGROUP

Microsoft introduced the HomeGroup concept in Windows 7. HomeGroups are designed to simplify the management of workgroups for administrators, particularly homeowners. Instead of requiring an administrator to manually set up shared user accounts on every PC, HomeGroup security settings can be managed through one shared login.

Additionally, HomeGroup communication is encrypted and makes it simple to share even single files with other HomeGroup users.

Joining a HomeGroup does not remove a PC from its Windows workgroup; the two sharing methods co-exist. Computers running versions of Windows older than Windows 7, however, cannot be members of HomeGroups.

The open source software package Samba (which uses SMB technologies) allows Apple macOS, Linux, and other Unix-based systems to join existing Windows workgroups.

Apple originally developed AppleTalk to support workgroups on Macintosh computers but phased out this technology in the late 2000s in favor of newer standards like SMB.