Business travellers need to make meetings at set times regardless of the number of time zones they cross. When people regularly wore watches, forgetting to adjust for time zones could cause them to miss appointments.
Now that increasing numbers of people use their mobile phones to tell time, this problem is disappearing. Phones get more from local cell towers than a connection – they also get the local time, which keeps the time displayed on phone screens properly synchronized.
You computer can also adjust its clock to another time zone, but it isn’t necessarily set up to automatically make this adjustment. These settings matter especially if you use electronic calendar invitations to schedule conference calls with people in other time zones. If they aren’t set correctly, the people you invite may have the event appear in their calendars at your time, not theirs.
Windows computer owners can find the right settings in the Windows Control Panel. Mac owners may want to check out the following video. (The key information Mac owners need is in the first minute and a half of the video.)
http://www.youtube.com/watch?v=NTWwF77VM3E