Why is there time differences?

Answer 1

Basically, because the world is round and it spins on it's axis and rotates around the sun.

Answer 2

Basically, you don't want it to be night time when you're having breakfast. You also don't want to have to go to school in the middle of the night. As the Earth rotates around the Sun, there needs to be a way to keep track of how long it takes to start the process all over again....this process has been determined to take 24 hours, thus accounting for time differences. This is why it's day time here in the Middle East on Wednesday afternoon and just after Midnight in The US on Wednesday morning.

Answer 3

For thousands of years, people simply measured time based on the position of the sun; at it's most basic - it was noon when the sun was highest in the sky.

This means that since the sun is not directly over-head in every place at the same moment, time from one city to another would be different. Sundials were used well into the Middle Ages. After mechanical clocks began to be invented, cities or towns would set their town clock by measuring the position of the sun, but every city was still on a slightly different time.

As a way to keep railroads running on a regular schedule - and to prevent collisions the idea of "standardized time" was invented.
Standard time zones can be defined by geometrically subdividing the Earth's spheroid into 24 lunes (wedge-shaped sections), bordered by meridians each 15° of longitude apart. The local time in neighboring zones is then exactly one hour different.
This matched the time to the Standard time in Greenwich (GMT). This location was chosen because by 1884 two-thirds of all charts and maps already used it as their Prime Meridian.

In order to make the clock match the actual day and night periods more closely during winter months in more northerly and more southerly latitudes "daylight savings time" was invented. This is because the period of daylight hours changes seasonally for people living more than about 20° north or south of the equator and the variation becomes more extreme the farther north or south you get from the equator.

Recently Daylight Savings time has been the subject of much adjustment - to allow automated systems for streetlights traffic controls and sprinkler systems to be safer and more effective.

While a system of Universal time (one which is the same for everyplace) has been adopted for use in mapping, aviation and telecommunications and variations have been developed for GPS applications and for related systems using Geoid. These systems do not relate to local time without complex calculations and so they are not used for mundane day to day purposes of most people's lives.

Answer 4

Because in the mid 1800s Sir Sandford Flemming devised 24 different time zones for the world to help with railroads so they'd deliver goods on time and allow farmers extra hours of daylight to plant and harvest their crops.

Answer 5

Because in the mid 1800s Sir Sandford Flemming devised 24 different time zones for the world to help with railroads so they'd deliver goods on time and allow farmers extra hours of daylight to plant and harvest their crops.

Answer 6

This is because of the shape of the Earth which effects the different times that the Sun hits the Earth.

Answer 7

Because the sun hits the earth at different times.

Answer 8

You know about the earth's rotation, don't you?
Well, if we were all on the same time, some countries would be experiencing 9am in the dark. Coming and going to school and work would be most inconvenient in the dark.