The book is colorful and ludic which is a good idea for a "Beginner's Guide". The layout is attractive, there are many detailed examples. I like the pedagogy: the author wants you to learn by doing. However, the book is poor as a reference: the coverage is limited despite the 300 pages and the chapter summaries are strictly non-technical.
It says how long ago something was said, so you can tell last month
from 2014 without doing the arithmetic. Full and green is recent; it
drains and cools as the date gets older, and empties completely at about
6 years.
5d5 days ago
8mo8 months ago
2yr2 years ago
4yr4 years ago
9yr9 years ago
A striped bar means the date itself is an estimate — the source did
not carry an exact one. An entry with no date at all gets no bar.