The AWK Programming Language

The AWK Programming Language (1988) https://archive.org/details/pdfy-MgN0H1joIoDVoIC7 Best as in best written, along with K&R—Brian Kernighan co-authoring both can't be an accident!—it's just a pleasure to read. I use it as a model when writing documentation myself. They get you started using AWK literally on page 1. Later they get into the details of particular use cases—profiling, making DSL interpreters/compilers, random text generation, making indexes, a graph-drawing language, databases, data validation etc etc. All in under 200 pages! And best as in most useful—I use AWK every day for all kinds of things–web scraping, rearranging and creating data for programs, meta-programming etc. So easy to make whatever tool's needed for a job.

+1. I have a corner of a bookshelf reserved for everything Kernighan, e.g. both Software Tools editions, both C Language editions, The Unix Programming Environment, The Practice of Programming, The AWK Language, even a copy of The Elements of Programming Style. I, and my employers and clients, may owe more to Mr. Kernighan for his teaching and programming style, than anyone else.