...It covers tools like grep, sed, awk, perl, Ruby one-liners, file attribute commands, sorting, tail/head/less/cat, and many more. It's intended as a learning resource, with explanations, examples, exercises, solutions. It is archived (read-only), but still serves as a large compendium of text processing patterns for Unix-like command line environments. Provides hands-on examples, exercises and solutions so learners can practice. Also has E-book versions (PDF/EPUB) of many chapters so content can be read offline or in nicer formatting.