What does a permissions setting that starts with the letter 'l' refer to?

A permissions setting that starts with the letter 'l' in the output of the ls -l command indicates that the file is a link. Specifically, it refers to a symbolic link, which is a special type of file that serves as a reference or pointer to another file or directory in the filesystem.

Symbolic links are used to create shortcuts or aliases to files and directories, making it easier to access them without needing to navigate the entire directory structure. When you see the 'l' at the beginning of the permissions string, it distinguishes symbolic links from other types of files, such as regular files or directories, which start with different characters ('-' for a regular file and 'd' for a directory). This distinction is crucial for users managing file systems, as it indicates the nature and functionality of the linked object within the filesystem.