A "large number" refers to a quantity that is significantly greater than what is typically encountered in everyday life. In mathematics, large numbers can be represented in various forms, such as millions, billions, or even trillions. These numbers are often used in fields like finance, science, and statistics to describe vast quantities or measurements. In practical terms, large numbers can be challenging to comprehend. For example, a billion is a thousand million, which can be difficult to visualize. To help understand large numbers, people often use comparisons, such as saying that a million seconds is about 11.5 days, while a billion seconds is roughly 31.7 years.