More users less bandwidth

By just using http compression and configuring the server not to send the same files (i.e. logo image) to the browser each time a new page is loaded, we can save you up to 75% of the bandwidth. This in turn either reduces your costs at your ISP or increases the amount of concurrent visitors you can receive.

Server caching

Both Apache and IIS allow for server caching, the process by which it saves the most viewed pages in memory or on a quickly access disk for faster retrieval than going back to the ASP.NET or PHP.

Back end db server tuning

Again the database server and its communications can be tuned to increase throughput or make store procedures run faster. This process is taken on a case by case basis, starting with the hardware configuration and moving forward through all of the OS and drivers, bringing them up to a level where they function best.