In this way, even though the author of a page uses font attributes to simulate headers, a user agent would be able to simulate moving through headers by matching the font attributes selected. The most significant advantage of this strategy is that it requires minimal understanding of the document structure and command structure by the user. When the user finds a document section that seems to contain the type of information of interest, a single command can move to the next similar element, regardless of the nature of the element under consideration. A second command would find the previous element, allowing two-way navigation throughout the document. Since the term may be located many screens down a document, such search facility adds significantly to the usability of a user agent.
Many authors use in-line markup to indicate elements of interest.
Key paragraphs may be formatted in a different font, or with different indenting. These techniques allow the visual user to quickly identify significant ideas while scanning through a document. To provide equivalent access to users with visual impairments, a user agent should provide the ability to search within a document based on the attributes of the text as well as the content of text.