The server might fetch those variables from a database and insert them before shipping the page. Using templates may require either custom programming or a third-party product. Another way to maintain page uniformity is to generate pages dynamically using scripts. Scripts allow you to generate a collection of pages using a set of arguments. For instance, an image catalog can be scripted so each page is uniquely identified by the image it displays then a server-side script determines what page the user wants and then creates it on demand.
Every page looks similar because the same script makes each page.
A site-wide change can be implemented simply by making changes to that script. Using scripts typically requires custom programming and places extra load on the server. However, scripts efficiently handle infinite permutations of content extracted from a database. Style Sheets Style sheets are becoming the preferred way to describe and maintain page appearance. A style sheet specifies how different elements look on the page.