Why do we have time zones and how do they work? - Presentation

Time zones are a fundamental concept in understanding how different parts of the world experience time. They are divisions across the Earth, delineated by imaginary lines known as meridians that run from the North Pole to the South Pole. At the heart of these time zones is the Prime Meridian, which passes through Greenwich in London, dividing the world into the eastern and western hemispheres. Countries located to the east of the Prime Meridian are ahead in time relative to the United Kingdom, while those to the west are behind. These time zones allow us to coordinate time across the globe, ensuring that there is a standard reference for when events occur and helping us to manage activities like international travel and business.

The necessity for time zones arises from the Earth's rotation on its axis, which results in varying exposure to sunlight across the planet. This rotation means that while some parts experience daylight, others are in darkness. To accommodate this, the world is segmented into 24 time zones, each representing one hour of the day. Larger countries may span across multiple time zones due to their extensive size, while smaller countries typically remain within a single zone. Understanding time zones is crucial for activities such as scheduling international meetings or travel. For instance, if it is 12 o'clock in the UK, the time in countries like India or Canada will differ, with some being hours ahead and others behind, depending on their position relative to the Prime Meridian.