The concept of the “first year of the world” is a complex one, as it depends on the context in which you are asking. From a scientific perspective, the Earth is estimated to be around 4.54 billion years old. This age is determined through radiometric dating of the oldest rocks and minerals found on Earth, as well as meteorites that have fallen to Earth.
However, if you are referring to the first year in a historical or cultural context, it varies widely depending on the civilization or calendar system. For example, the Gregorian calendar, which is widely used today, marks the year 1 AD as the first year following the traditionally recognized birth of Jesus Christ. Other cultures and religions have their own calendars and starting points, such as the Hebrew calendar, which dates back to 3761 BCE, or the Islamic calendar, which begins in 622 CE.
In summary, the “first year of the world” can be interpreted in different ways depending on whether you are looking at it from a scientific, historical, or cultural perspective.