Which protocol is primarily used for file sharing in Windows environments?

The Server Message Block (SMB) protocol is the primary protocol used for file sharing in Windows environments. SMB allows applications to read and write to files and request services from server programs in a computer network, effectively enabling shared access to files, printers, and serial ports among nodes on a network.

In Windows, SMB is integral to operations such as accessing networked files and printers, facilitating operations that are seamless for users in a Windows domain or workgroup. It operates at the application layer and is designed specifically for local area networks. Moreover, SMB provides a way for an application to communicate with files through a network, thus making it critical for file sharing.

While NFS (Network File System) is also a file-sharing protocol, it is primarily utilized in Unix and Linux systems rather than Windows. FTP is a standard network protocol used for transferring files but is less integrated into the Windows file sharing experience than SMB. Lastly, HTTP is primarily used for transmitting hypertext over the web and is not designed specifically for file sharing in a network context like SMB. Thus, SMB is definitively the correct choice for file sharing in Windows environments.