If you have an HTML site, in all probability it uses a very small amount of resources because it's static, but this isn't the situation with dynamic database-driven Internet sites that use PHP scripts and offer you considerably more capabilities. This type of websites produce load on the hosting server anytime someone browses them, since the server requires time to execute the script, to access the database and then to supply the information requested by the visitor's web browser. A widely used discussion board, for example, stores all usernames and posts inside a database, so some load is produced every single time a thread is opened or a user looks for a certain name. If many people access the forum all at once, or if every search involves checking hundreds of thousands of database entries, this can generate high load and affect the overall performance of the Internet site. In this regard, CPU and MySQL load stats can give you information about the site’s overall performance, as you can compare the numbers with your traffic stats to decide if the Internet site needs to be optimized or moved to a new kind of web hosting platform that'll be able to bear the high system load in case the site is very popular.