A solid-state drive (SSD) is a media which uses flash modules to store information. The SSDs are still relatively new and more expensive compared to standard hard disk drives (HDD), but they're considerably faster, so they are ordinarily employed for Operating Systems and applications on both personal computers and web hosting servers. An SSD is recommended because it does not have spinning disks which limit its speed and can even cause overheating like it could happen with an HDD. A number of companies employ SSDs for caching purposes, so all site content that is accessed more often will be kept on this type of drives, while all other content will be kept on regular HDDs. The main reason to use this kind of a configuration is to balance the cost and overall performance of their web hosting platform and to minimize the load on the HDDs caused by countless reading and writing processes.