They are on completely different parts of the world. When it is daytime in Greece it is night in the US, so they have to have different times and so they are in different time zones.
Central Time Zone, Pacific time zone AND Atlantic time zone. - Anonymous Canadian
There is different parts that have time zones
4 hour's ahead
The Mountain time zone is between the Pacific and the Central time zones.
The Central Time Zone is east of the Mountain Time Zone.
Pacific Standard Time zone
US Eastern Time Zone
Most of Texas is in the US Central time zone. A small part of western Texas is in the US Mountain time zone.
the eastern time zone
Maine is in the US Eastern time zone.
Waterloo, Iowa is in the US Central Time Zone.
No US states are in the Atlantic time zone. The only parts of the US in the Atlantic zone are the territories of Puerto Rico and the US Virgin Islands.