files

A file is a named collection of data stored on a storage device. It is a discrete unit that can contain text, images, executables, or other data, and is accessed by a path that specifies its location within a file system.

Files are identified and managed within a file system, which records their names, sizes, types, permissions, and timestamps. Directories serve as containers that organize files hierarchically.

File formats define how data is organized and interpreted. Text files store human-readable characters; binary files contain non-text data. Extensions or MIME types indicate format, but not all files have one.

Common operations include creating, opening, reading, writing, appending, renaming, moving, copying, and deleting. Access depends on permissions and ownership.

Permissions and security: On most systems, files have an owner and belong to a group, with permission bits that grant read, write, and execute rights. Access Control Lists can specify finer rules.

Files also carry metadata such as size, creation and modification times, and sometimes checksums or version information. Backups and versioning preserve history.

Storage considerations: File fragmentation and device type affect performance; modern systems use journaling, solid-state optimization, and deduplication. Users should organize files with meaningful names and backups.