Which one is correct: lakh or lac?

 Both "lakh" and "lac" are used to denote the same number in the Indian numbering system, specifically representing one hundred thousand (100,000). However, "lakh" is the more commonly used term in India and is considered the standard spelling in official contexts and publications. "Lac" is less common but is also used informally in certain regions or contexts.

In summary, while both terms refer to the same numeric value, "lakh" is generally preferred and considered more standard in usage.