We can thank the Babylonians for our seven-day week.
Waiting for the weekend can often seem unbearable, a whole six days between Saturdays. Having seven days in a week has been the case for a very long time, and so people don’t often stop to ask why.
Some of the earliest civilizations observed the cosmos and recorded the movements of planets, the Sun and Moon., who lived in modern-day Iraq, were astute observers and interpreters of the heavens, and it is largely thanks to them that our weeks are seven days long. The Babylonians divided their lunar months into seven-day weeks, with the final day of the week holding particular religious significance. The 28-day month, or a complete cycle of the Moon, is a bit too large a period of time to manage effectively, and so the Babylonians divided their months into four equal parts of seven.
However, the Babylonians were such a dominant culture in the Near East, especially in the sixth and seventh centuries B.C., that this, and many of their other notions of time — such as a 60-minute hour — persisted.