银行是以存款、贷款、电汇、储蓄等业务，承担信用中介的金融机构。

一般认为最早的银行是在意大利的威尼斯，而德国在汉堡、英国在伦敦也相继设立了银行。十八世纪末至十九世纪初，银行得到了普遍发展。

在宋朝时期中国出现了具有高利贷性质及无利息存款业务的钱庄与票号，第一家具有近代特征的银行是上海中国通商银行，1897年（光绪二十三年）成立。在汉语“银行”一词当中，“银”往往代表的就是银钱，而“行”则是对大商业机构的称谓。把办理与银钱有关的大金融机构称为银行，在中国最早见于太平天国洪仁玕所着的《资政新篇》。

A bank is a financial institution that accepts deposits from the public and creates credit. Lending activities can be performed either directly or indirectly through capital markets. Due to their importance in the financial system and influence on national economies, banks are highly regulated in most countries. Most nations have institutionalized a system known as fractional reserve banking under which banks hold liquid assets equal to only a portion of their current liabilities. In addition to other regulations intended to ensure liquidity, banks are generally subject to minimum capital requirements based on an international set of capital standards, known as the Basel Accords.