A solid-state drive (SSD) improves the performance of each app running on it when compared to a common hard-disk drive (HDD). The reason is that a solid-state drive uses a variety of interconnected flash memory modules, so there are no physical parts to move. In contrast, an HDD works by using spinning disks and every reading or writing process causes the disks to spin, so the speed of an HDD is limited. Since the prices of the two types of drives also differ, a lot of PCs and web servers are equipped with an SSD for the operating system and various applications, and a hard-disk drive for data storage, this way balancing cost and performance. An Internet hosting service provider may also use a solid-state drive for caching purposes, so files that are accessed very often will be kept on such a drive for reaching improved loading speeds and for reducing the reading/writing processes on the hard drives.