HTML Validators
View tools in the HTML Validators category
Intended purpose: The primary purpose of this category of product is to check that the syntax of the HTML tags in a document are legal according to one or more of the HTML protocol standards. Some validators add further functions, such as editing capabilities and help systems.
Potential for remote management:
Limited. Historically, the two major browsers, Netscape and Internet Explorer, have handled invalid syntax rather forgivingly, allowing some tags to be unclosed, for example. Writers of web pages have not been held accountable for many mis-uses of the markup language.
Why do we care?
A well-formed and valid HTML page is probably an indicator of a content provider or web developer who cares about strict markup. But such a page is not by itself an indicator of a stable site. Conversely, a laxly-tagged page is not by itself an indicator of a site at risk. Nevertheless, taken with other indications of careless management, the validity of the HTML might indicate a site with potential for problems.
Characteristics?
All HTML validators parse HTML pages and report on the validity of the use of the tags. Some also include the capability of validating CSS constructs. Many peripheral functions are possible—editing, linking error messages to the errors they describe, and glossaries of tag attributes, for example.
Relationship to other categories: (should this category be used
in conjunction with another category?)
HTML Validators should be used with other tools if one's purpose is to assess the health of a site. See the Why do we care? section.
High or Low impact:
Low. Most validators examine a page at a time, allowing for user interaction and intervention. If a web crawler had a built-in, real-time validity analyzer, the possibility could exist that the tool would be a heavy bandwidth user, but we are unaware of any validators of this type.
Can these tools be used on other sites or only on your own site?
Validators can be used both locally and on remote sites. Their primary function is to allow a web developer to check the syntax of his or her own pages. Online validators can be pointed at remote URLs however. Downloaded pages are also candidates for inspection.
