The family are transported to the 1980s and have to decide what computer they are going to have for their house. Which one will they decide?
The Markup Validation Service by the World Wide Web Consortium (W3C) has confirm HTML documents for conformance to HTML or XHTML standards.comparing the mark-up on a web page to the W3C standards. The standards vary depending upon the declared version and so the validator will start by reading the DOCTYPE declaration to see which set of standards to apply.