The logrotate linux utility automatically compresses your ever-growing production log files.
If you encountered an error and wanted to search the history including all compressed logs, you may have considered unzipping all of them into a directory and run a grep in that directory.
Fortunately linux offers a more idiomatic way for grepping gzipped files:
From the manual:
zgrep, zegrep, and zfgrep act like grep, egrep, and fgrep, respectively, but accept input files compressed with the compress(1) or gzip(1) compression utilities.
h/t Jack ChristensenTweet