Extending tags for information resources

A method for extending a tag of an information resource in an information network may be provided. The method may include providing a group of tags, stored in a database, in a user interface, and selecting at least one tag out of the group of tags and linking the tag to an information resource using the user interface. Furthermore, the method may include extending the tag, such that the resulting extended tag may be a semantically structured string of characters building a first expression including a first operand, a first operator and a first value, wherein the tag may be the operand, such that the extended tag is machine-interpretable by a parser, such that the information resource may be tagged with the machine-interpretable, extended tag.