The digital picking system (DPS) uses light modules instead of invoices or order lists on paper. It is a paperless operation to place or put goods. The word comes from a combination of Japanese and English words. It is used widely to support distribution of goods. The picking operation is called pick-to-light and the putting operation is called put-to-light. In Japan, both operations are often called Digital Picking Systems, but originally only the picking operation was called digital picking system, and the assorting operation was called assorting system (DAS: Digital Assorting System). The following are various operations that support digital picking.
- Digital Picking Systems

A light-directed order fulfillment system means using digital light modules to pick or take out items from a stored location to fulfill an order for delivery.
- Put-to-light system

The put-to-light system is sometimes called the "planting seeds" system. It is an operation that involves putting goods into containers according to the order or address to be delivered.
- Inventory Support Systems
- It supports the inventory operation by displaying the quantity of stock stored in the computer on the light module.
- Putting / Replenishment Systems
- A system that supports replenishment of goods by providing instructions to light modules.
- Parts Supply Systems
- A system that provides instructions to light modules to pick necessary parts according to the production plan in an assembly line.
- Assembly Support Systems
- A system that supports assembly operations by sending instructions based on the assembly orders to light modules installed at the warehouse.
