yellow means "zone of equal hour related to GMT", pink means "zone of unequal hour related to GMT", Orange means "split hours" (eg GMT+ 5.30) and i think Green means "individual local time"
So pink is GMT+/- and odd number
Yellow is GMT+/- an even number
Orange is GMT+/- a half hour
Green is their own time zone all year round???
(i think)
Nope, The States Pacific Coast is in PDT now (or Pacific Daylight Time) and we are in BST (British Summer time) or IST (Irish summer time where i am). So this means they are still 8 hours behind us, not 9 like they were ONLY for a few days, because Europe and the US implement Daylight Savings Time at a slightly diferent time. (i think there is only a few days between it)
So 9.30am PDT = 5.30pm BST
PDT = GMT - 7hours
BST = GMT + 1 hour