Programming Forth introduces you to modern Forth systems. In 1994 the ANS Forth standard was released and unleashed a wave of creativity among Forth compiler writers. Because the ANS standard, unlike the previous informal Forth-83 standard, avoids specifying implementation details, implementers took full advantage. The result has been what I choose to call modern Forths, which are available from a range of sources both commercial and open-source.
Not the best Forth book, but a fine overview of Forth with some interesting insights into embedded systems. It has a quick tutorial which advances too fast for a beginner but goes quite far into more advance features, specially meta-programming and immediate words. The book is short enough to be worth reading if you are interested in the topic.