| Term | Definition |
| I/O Unit | See – Input / Output Unit. |
| Importing | To bring data or a file from one program or system to another. |
| Input / Output Unit | A device that is designed only to input and/or output information, not to process it.Example: A modem. It relays data (inputs and outputs), but has no other function. |
| Integration | Combining software or hardware components or both into an overall system. |
| Interactive Communications | A term describing a program whose input and output are interleaved, like a conversation, allowing the user's input to depend on earlier output from the same run. The interaction with the user is usually conducted through either a text-based interface or a graphical user interface. Other kinds of interface, e.g. using speech recognition and/or speech synthesis, are also possible. This is in contrast to batch processing where all the input is prepared before the program runs and so cannot depend on the program's output. |
| Interface | The device or program that allows the computer to communicate with the user or with any other entity.Example: The ports and connectors are the interface that allows the computer to communicate with the printer. Microsoft Windows uses interfaces to make it easier for the user to communicate with the computer by not requiring memorization of commands or computer languages. |
| International LDS | The INT LDS and the POS act independently. Poured drinks are posted to a PC file as debits, while the offsetting credits are posted once the drink is posted to the guest check. If communications are interrupted between the POS and the LDS, the bartender can continue to pour drinks. |
| Inventory | Used as a noun (as in “a standing inventory”), it refers to the stock on the shelves.Used as a verb (as in “inventorying all dry goods”), it refers to the counting of that stock. |
| IP Address | Internet Protocol Address. A unique numerical sequence that serves to identify a computer. |
| ISL | Interface Script Language. This allows a programmer to customize the way the POS operates. |
| Item Discount | Discounts that can be applied to specific menu items. |
| Item Priority | Assigned to menu items in order to control the order in which they are displayed or printed. An operator may enter items in any order, prioritizing will cause them to be rearranged before printing. |
| Itemizers | A means of grouping subtotals of like transactions. Various subtotal discounts, service charges, or taxes may be applied to all or only certain itemizers.Example: Itemizers can be thought of as collection buckets where all food items might be totaled up in one bucket, and all liquor items in another |