A standard compliant website will conform to the W3 consortium recommendations, which makes for the proper website coding compliance. There is a W3 school, which features tutuorials, plans, and other techniques to teach developers and coders, the proper techniques, and the proper HTML format, which are in line with the latest standards, and the latest drafts of Internet Explorer, Firefox, or whatever other operating system and internet connections are used by the site hosts.
The first thing to consider is the markup language. This is the XML and HTML tags, which must comply with the W3 rules, depending on the browser being used. Using the proper language will ensure the site looks the same, no matter which browser a visitor is on, and will have the same markup language on all the browsers which are available to the internet user. The rule requires that all tags, letters, attributes, and values are in lowercase letters, except for DOCTYPE, which must be capital.
The next rule is that all DOCTYPE documents be at the top of the document. This will allow for the uniformity of the site, no matter what browser a visitor is using. It will ensure that all the language on the site is going to be the same, whether the user is on Internet Explorer, or whether they are using Google Chrome to browse the web, and visit that site.
Next, all XHTML tags have to be closed. If there is not end tag, the site will offer different features on different browsers. All tags also have to be properly nested, and there cannot be any attribute minimization. The tags must also begin with , in order for the site to appear the same in all browsers.
The W3 school is the best place to find the tutorials, and to learn the proper setup of your W3C compliant site.