In programming, a socket is an endpoint of a communication between two programs running on a network. Sockets are used to create a connection between a client program and a server program. Sockets API is available in the Node. js net module.
A HEAD request is an HTTP GET request without a message body. The header of a request/response contains metadata, such as HTTP protocol version or content type.
A head request is issued with the HEAD command followed by the resource URL and HTTP protocol version. Note that the \r\n are mandatory part of the communication process. The details are described in RFC 7231 document.