Dynamic websites are generated on the fly and use server-side technology to generate webpages. They typically extract their content from one or more back-end databases: some are database queries across a relational database to query a catalogue or to summarise numeric information, others may use a document database such as MongoDB or NoSQL to store larger units of content, such as blog posts or wiki articles.
When dynamic web pages first developed, they were typically coded directly in languages such as Perl, PHP or ASP. Some of these, notably PHP and ASP, used a 'template' approach where a server-side page resembled the structure of the completed client-side page and data was inserted into places defined by 'tags'. This was a quicker means of development than coding in a purely procedural coding language such as Perl.