Sunrise

There are 24 time zones around the world.  The day starts at Kiribati Islands.  It continues to places like Tonga, Chatham Islands, New Zealand, Norfolk Island, New Caledonia, Lord Howe Island, Tasmania, South Australia, Japan, China, Thailand, Myanmar, Bangladesh, Pakistan, Oman, Egypt, Sweden, Britain, Azores, Sandwich Islands, Argentina, Newfoundland, Bolivia, Florida, Illinois, Colorado, Oregon, Juneau, Marquesas Islands, Hawaii, and Samoa.  The day ends at Baker Island.  China extends over 5 time zones but the entire country uses the same time.  All of India also uses the same time but it is 1/2 hour off from the countries around it.  There is nautical time, Newtonian time, Julian time, International Atomic time, and mean solar time.  All of these times are basically synodic times - based on the rotation of the earth in relation to the sun.  There is also sidereal time which is oriented to the stars.  I could go on but you can see how confusing adding in Daylight Saving Time might be on a person's schedule. 

(Use this argument to explain to the pastor why you are an hour late for church on Sunday.)