gunzip
Transfer and archivesPackage: gzip
Decompresses a .gz, replacing the archive with the file. gunzip -c writes to standard output without touching the archive, which lets you read a rotated log without unpacking it to disk.
What its options do in the lessons
From the same glossary the lessons render under their commands, so the two cannot disagree.
gunzip -c- Writes to standard output and leaves the compressed file untouched, so it can be piped straight into another command.