Globbing is shell pattern expansion: the shell turns wildcard patterns such as *, ?, and [a-z] into matching filenames before a command runs. For example, rm *.tmp may expand to every file ending in .tmp in the current directory. This is convenient, but it can also be surprising because the shell decides what matches, not the program you typed.
In cyber security, globbing matters because it can change which files are touched, copied, deleted, or parsed in automation. A careless cleanup script can delete more than intended, and an attacker who can influence filenames may exploit wildcard handling to trigger unsafe behavior or confuse log processing. Defenders test globbing carefully in backup jobs, incident-response scripts, and admin tools, especially when filenames may contain spaces, leading dashes, or unusual characters. Safe shell work often means quoting variables and validating paths instead of relying on implicit expansion.