Captchas are little boxes on webpages which show a squiggly set of letters and numbers that the user isrequired to transcribe correctly in order to register or enter the site.

• 验证码就是出现在网页上那些小小的方框，里面显示了一组组弯弯曲曲的字母和数字，而用户则被要求正确誊写这些字母和数字，以此进行注册或者登陆帐户。