Rel is a program that determines the relevance of text documents to a set of keywords expressed in boolean infix notation. The list of file names that are relevant are printed to the standard output, in order of relevance. The boolean logical operators supported are, "&" for logical "and," "|" for logical "or," and "!" for logical "not." Parenthesis are used as grouping operators.
The forward relationship also known as the "link type". It specifies a named relationship from the enclosing document to the resource specified by the HREF attribute. HTML link relationships are as yet unstandardized, although some conventions have been established. Here are some proposed/used relationship values: Value Description
A relation, i.e. a logical predicate, of an atom (Atom). It is optionally surrounded by an operator (op). Attributes: @uri(See: atom module)