LPI-Japan, which is an organization that promotes the spread of Linux in Japan is distributing
"Standard Linux Text Book" with free.
The English version of the Linux standard textbook can be read from this site.
We will answer those who are wondering "Why from this site?"
This is because when President Kanno was dispatched to Sri Lanka as a senior volunteer of the JICA Japan Overseas Cooperation Volunteers, he translated the "Linux standard textbook" as part of his activities. For that reason, please forgive the quality of volunteer level.