| Original author(s) | Douglas McIlroy |
|---|---|
| Developer(s) | AT&T Bell Laboratories |
| Initial release | January 1979 |
| Written in | C |
| Operating system | Unix, Unix-like, Plan 9 |
| Platform | Cross-platform |
| Type | Command |
| License | coreutils: GPLv3+ Plan 9: MIT License |
join is a command in Unix and Unix-like operating systems that merges the lines of two sorted text files based on the presence of a common field. It is similar to the join operator used in relational databases but operating on text files.