二百 (èr bǎi) is a numeral meaning 'two hundred' and functions as a cardinal number in Chinese. It combines the character 二 (èr), meaning 'two', and 百 (bǎi), meaning 'hundred'. Unlike English, Chinese numerals follow a strict multiplicative structure: the multiplier (èr) comes before the base unit (bǎi), with no word for 'and' or hyphenation. It is used in counting, measurements, prices, ages, and quantities — for example, '200 people', '200 yuan', or '200 years ago'.

This form is standard in both spoken and written Mandarin and appears frequently in daily contexts like shopping, travel, statistics, and time expressions. Note that 二百 is not used when stating years (e.g., '2023' is èr líng èr sān, not èr bǎi èr sān); for years, Chinese uses individual digits. Also, in formal writing or large numbers, 二百 may be replaced by 两百 (liǎng bǎi) before measure words, but 二百 remains common and correct in neutral contexts like standalone counts or after measure words like 个, 只, or 元.