Data input can happen in several ways. One way is as the result of data entry. In data entry, data is placed in chosen fields of a database by a human agent using a device such as a mouse, keypad, keyboard, touch screen, or stylus, or alternatively, with speech recognition software. Data capture is a kind of data input in which there is no data entry. Instead, data is collected in conjunction with a separate activity.

One of the devices involved in data capture includes supermarket checkouts equipped with barcode readers. Barcode readers are electronic devices that use a laser beam to scan a barcode. These readers are categorized as non-contact automatic data capture devices. They need to be within a few inches of the material they are scanning to read it.

Magnetic stripe readers, also called card swipe machines, collect the information stored in the magnetic material that is found on bank, charge, and credit cards. This information often includes an account number, the customer’s own identification number, and other information. ATMs can also read this information. If the magnetic stripe is damaged or exposed to a strong magnetic or electrical field, the information will not be retrievable.

A point-of-sale (POS) terminal, through which credit card transactions are submitted and validated, reads the bank name and customer account number of a card swiped through a magnetic stripe reader. If the bank responds that the funds are available, the POS terminal transfers the approved amount to the account of the seller, finishing the transaction with a printed receipt.

Optical character recognition (OCR) involves the conversion of a digitized image of text created in print or handwritten to characters that are recognizable by word-processing programs. It is also used to preserve documents in an electronic format without having to re-enter data by hand.

Radio frequency identification (RFID) is a data capture technology in which identification of items is done through transponders that are attached to them. A transponder is a type of radio-relay equipment that is passive. Its function is to passively respond with a repetition of the original signal or a coded recognition signal when struck by an initiating signal. RFIDs work from greater distances than barcode readers can, which is one of their values.