Abstract: A memory content is cleared by a clear signal which is formed from a combination of input information known by only a specified person. Said clear signal is developed by a combination of keyswitch inputs, or a combination of a keyswitch input and dial switch input, which dial switch is spatially separated from a clear unit.

Abstract: An information retrieving apparatus comprises a memory having a plurality of records stored therein which are formed with weights attached to items of information, a reader for reading the stored information out from the memory, input means for entering an interrogation to be checked with the information in the memory, comparing means for detecting coincidence between the information read out by the reader and the signal, discrimination means for determining, in accordance with the coincidence detected by the comparing means, the weight of the information read out by the reader which is coincident with the interrogation, and selector means for selecting, in accordance with the weight decided by the discrimination means, a certain item of information from the record to which the information coincident with the interrogation appertains.