Standards are rules for writing 'good' code which every browser can understand and run in a similar way to get a standard result.

Web sites are written in a language called HyperText Markup Language (HTML). The way web pages look is often controlled by Cascading Style Sheets (CSS). This sounds complicated but it is just simple text interlaced with instructions for the browser and are usually quite easy to understand. For example the html instruction to make something bold looks like <b>and to stop it being bold is </b>. The text files are not saved with a .txt file extension but with .htm or .html.

In the past these files were often badly written and your browser had to work out what it was supposed to do. Different browsers produced different results. Nowadays any good developer knows all the correct standards to follow and writes ‘good’ standard compliant code. This is a bit like being able to write a concise business letter without spelling and grammar mistakes. Unlike humans who can guess at what was meant by a badly written letter, computers still often guess wrongly. That is why it is increasingly important to follow standards.

Not all web pages are written in advance. Often web servers (which store the websites) are asked to make a web page on the fly from a database. This is done by using a computer program or a script and mixing html with information taken from the database. Many different languages can be used to do this. Two of the most common are called ASP or PHP and they often use MSQL or MySQL as a database (SQL means Select Query Language.) All these languages have standards too. Sometimes if standards aren’t followed with these languages the computer can output complete rubbish or nothing at all.