# look > Display lines beginning with a prefix in a file. > Note: the lines in the file must be sorted. > See also: `grep`, `sort`. > More information: . - Search for lines beginning with a specific prefix in a specific file: `look {{prefix}} {{path/to/file}}` - Case-insensitively search only on blank and alphanumeric characters: `look {{-f|--ignore-case}} {{-d|--alphanum}} {{prefix}} {{path/to/file}}` - Specify a string termination character (space by default): `look {{-t|--terminate}} {{,}}` - Search in `/usr/share/dict/words` (`--ignore-case` and `--alphanum` are assumed): `look {{prefix}}` - Search in `/usr/share/dict/web2` (`--ignore-case` and `--alphanum` are assumed): `look {{-a|--alternative}} {{prefix}}`