The variety of weeks in a yr can range relying on the calendar system used. The Gregorian calendar, which is essentially the most extensively used calendar on the earth, has 52 weeks in a regular yr and 53 weeks in a intercalary year. A intercalary year is a yr that’s divisible by 4 however not by 100, or a yr that’s divisible by 400. The yr 2025 will not be a intercalary year, so it’ll have 52 weeks.
The Gregorian calendar was launched in 1582 by Pope Gregory XIII to right errors that had accrued within the Julian calendar, which was the calendar that was used beforehand. The Julian calendar had a intercalary year each 4 years, which brought about it to float out of sync with the photo voltaic yr. The Gregorian calendar corrects this by having a intercalary year each 4 years, apart from years which can be divisible by 100 however not by 400.