A web document is similar in concept to a web page, but also satisfies the following broader definition by W3C:

Every Web document has its own URI. Note that a Web document is not the same as a file: a single Web document can be available in many different formats and languages, and a single file, for example a PHP script, may be responsible for generating a large number of Web documents with different URIs. A Web document is defined as something that has a URI and can return representations (responses in a format such as HTML or JPEG or RDF) of the identified resource in response to HTTP requests. In technical literature ... the term Information Resource is used instead of Web document.