Ma'anar ƙamus na kalmar "bayani" tana nufin tsarin tambayoyi ko bitar mutum ko ƙungiyar mutane, yawanci bayan wani aiki ko aiki, don samun bayanai, ra'ayi ko darussan da aka koya. Tattaunawa ce da aka tsara don tattara bayanai da fahimta game da gogewa, aiki, nasarori, ƙalubale, da yuwuwar wuraren ingantawa. Ana amfani da bayyani sau da yawa a cikin mahallin kamar soja, hankali, tilasta doka, da jirgin sama don sauƙaƙe koyo, haɓaka aiki, da haɓaka aminci.