A solid-state drive (SSD) improves the performance of any application running on it when compared to a common hard-disk drive (HDD). The reason is that a solid-state drive uses a number of interconnected flash memory modules, so there're no physical parts to move. In comparison, an HDD functions with spinning disks and any reading or writing process causes the disks to move, so the speed of an HDD is limited. As the prices of the two kinds of drives are also different, a large number of desktops and web servers are set up with an SSD for the operating system and various applications, and a hard disk for data storage, thus balancing cost and efficiency. A website hosting service provider may also use an SSD for caching purposes, which means that files that are accessed regularly will be held on this type of a drive for accomplishing higher loading speeds and for limiting the reading/writing processes on the hard disks.