I am reading and taking notes on the HTML specifications for 100 days as part of #The100DayProject. Read the initial intent/backstory. I am a Microsoft employee but all opinions, comments, etc on this site are my own. I do not speak on behalf of my employer, and thus no comments should be taken as representative of Microsoft's official opinion of the spec. Subsections not listed below were read without comment.
So, I skipped out on spec reading for an entire weekend, Friday–Sunday. Oops. Currently reading in 2.4 Common microsyntaxes, dates and times.
188.8.131.52 Global dates and times
A global date and time (on the Gregorian calendar) smashes together year, month, date, hour, minute, second, and fraction of a second. Unlike other time microsyntaxes covered on previous readings, this one actually does include the time zone offset.
TIL that UTC, the current time zone structure, was created in the "mid-twentieth century". On times preceding UTC:
Time before the formation of time zones must be expressed and interpreted as UT1 times with explicit time zones that approximate the contemporary difference between the appropriate local time and the time observed at the location of Greenwich, London."
Who ever decided weeks should be seven days? So awkward.
A week in HTML-spec land is European: it starts on a Monday (as it does in my heart). Each week in the year gets a consecutive number, starting with 1 (sorry nerds). There's some guidance about when a year has 52 or 53 weeks.
The week string is in ISO format, like this: 2015-W03, where the two digits at the end are that week number described above.