What are web standards?

Essentially a web standards compliant website uses an hypertextual structure made of valid xhtml, html and css code according to the world wide web consortium requirements.

This w3c consortium provides a web service that easily validates your web page and states if they are web standards compliant or not:
http://validator.w3.org/

A good web project has also to achieve a good degree of accessibility: as many people as possible will be able to access all the information contained into the website and will be able to interact with the services hosted by your website.

Many web designers do not take care of the web standards rules or accessibility essentially because the large majority of commitments usually do not understand and appreciate the effort to build an accessible website; usually they appreciate and consequentially want to invest more money into a more graphical appealing website.
This is a great mistake because a good degree of accessibility assures an easy integration with world wide web, more visitors, a better access to search engines into your pages and contents.
Good accessibility means also that your website will last longer.

Accessible is far better!