Abstract: A simple data input apparatus is equipped with a magnetic card reader and uses an input guide sheet. The input guide sheet has such input items as service number, commodity number, quantity and unit price printed thereon and includes a magnetic strip storing the order in which these items are to be indicated. The simple data input apparatus is provided with an input guide section on which a plurality of indicating lamps are arranged. The data stored on the magnetic strip of the input guide sheet are read by the magnetic card reader and written into a RAM provided inside the apparatus. The input guide sheet is then placed on the input guide section and the indicating lamps light sequentially in accordance with the input item indication order written into the RAM from the magnetic strip.