I haven't read the book, but I've got a good idea what they are by reading online. They're times when babies are going through developmental changes that aren't necessarily growth spurts. Like if they learn a new skill rolling, using their arms better, etc. They're supposed to be predictable periods of fussiness and calmness. It can be confusing because they're measured based off of your due date, not your baby's birthdate. So my LO was almost a week overdue according to my DD. Thus when I'm looking at the chart, I'd look at week 11 instead of week 10. You can Google image search the chart.
Re: wonder week?