diskspace

Disk space refers to the amount of storage capacity available on a computer’s storage devices or logical volumes for storing files, programs, and data. It is typically described in terms of total capacity, used space, and free or available space. Storage is measured in units such as bytes and multiples (kilobytes, megabytes, gigabytes, terabytes) or, in binary-based units, kibibytes, mebibytes, gibibytes, and tebibytes.

Disk space is managed by the filesystem, which organizes data into blocks or clusters and maintains metadata about files. Formatting a volume reserves space for filesystem structures, and many systems reserve a portion of space for system use or root access. Free space is the portion not currently allocated to files, while available space may be lower when some space is reserved for privileged processes or system overhead.

Operating systems provide tools to monitor disk space. On Unix-like systems, commands such as df and du report usage by filesystem; on Windows, Disk Management and File Explorer display capacity and usage. Administrators plan storage by estimating growth, removing unnecessary files, compressing data, and moving infrequently accessed data to secondary storage or networked solutions.

Fragmentation and performance considerations vary by media. Magnetic hard drives can experience performance impacts from fragmented free space, while solid-state drives rely on wear leveling and TRIM to maintain efficiency. Defragmentation is generally not recommended for SSDs.

Common issues arise when disk space runs low, including failed saves, backup errors, and truncated logs. Remedies include deleting or archiving files, relocating data, expanding capacity, or migrating data to external or cloud storage.