Is it ensure, insure, or assure?
late 14c., "act of informing," from Old French informacion, enformacion "information, advice, instruction," from Latin informationem (nominative informatio) "outline, concept, idea," noun of action from past participle stem of informare (see inform). Meaning "knowledge communicated" is from mid-15c. Information technology attested from 1958. Information revolution from 1969.