Logging information
All UNIX systems have their own log files for writing logging information that comes from running servers and programs. Usually, most system log files of a UNIX system can be found under the /var/log directory. However, the log files of many popular services, such as Apache and Nginx, can be found elsewhere, depending on their configuration.
Logging and putting logging information in log files is a practical way of examining data and information from your software asynchronously either locally or at a central log server or using server software such as Elasticsearch, Beats, and Grafana Loki.
Generally speaking, using a log file to write some information used to be considered a better practice than writing the same output on screen for two reasons: firstly, because the output does not get lost as it is stored on a file, and secondly, because you can search and process log files using UNIX tools, such as grep(1), awk(1), and sed(1), which cannot...