grep 80+ tested grep examples: recursive search, regex flavours, context lines, counting, scripting, and more.
sed Tested sed examples: substitution, addressing, deletion, in-place editing, and multi-command scripts.
find Tested find examples: name and type filters, size and age, permissions, -exec vs -delete, and safe scripting patterns.
tar Tested tar examples: create, list, and extract archives, choose a compression format, and verify integrity.
curl 80+ tested curl examples: GET/POST/PUT/DELETE, headers, auth, cookies, uploads, redirects, retries, and scripting.