What year was the first calculator made ?
the first calculator to have a controlled carry mechanism which allowed for an effective propagation of multiple carries the first calculator to be used in an office ( his father 's to compute taxes ) the first calculator commercialized ( with around twenty machines built ) the first calculator to be patented ( " royal privilege " of 1649 ) the first calculator to be described in an encyclopaedia ( Diderot & d'Alembert , 1751 ) : the first calculator sold by a distributor :