There are various ways to classify shelves. The following are some common classification standards and specific types:

1. Classification by Development History

- Traditional shelves: including shelving units, layered shelves, drawer shelves, cabinet shelves, U-shaped shelves, cantilever shelves, grid shelves, saddle shelves, gas cylinder shelves, tire-specific shelves, etc.
- New shelves: such as rotating shelves, mobile shelves, shuttle shelves, assembled shelves, adjustable shelves, pallet shelves, drive-in shelves, high-bay shelves, mezzanine shelves, gravity shelves, and screen-mounted shelves, etc.

2. Classification by Applicability

- General-purpose shelves: suitable for various scenarios.
- Special-purpose shelves: designed for specific industries or items, such as pharmacy shelves and convenience store shelves.

3. Classification by Manufacturing Material

- Steel shelves: strong load-bearing capacity, widely used.
- Reinforced concrete shelves: often used in special environments, such as places with high fire and moisture resistance requirements.
- Wooden shelves: lower cost, suitable for storing lightweight items.
- Steel-wood composite shelves: combining the advantages of steel and wood, balancing strength and aesthetics.

4. Classification by Degree of Enclosure

- Open shelves: no top or side panels, suitable for well-ventilated warehouses.
- Semi-enclosed shelves: partially enclosed (such as with side panels but no top), balancing dust prevention and ventilation needs.
- Enclosed shelves: completely enclosed, suitable for occasions with high requirements for dust and moisture prevention.

5. Classification by Structural Features

- Shelving/grid shelves: basic form, composed of uprights and beams, suitable for placing conventional goods.
- Cabinet/drawer shelves: with cabinet doors or drawers, facilitating the classification and management of small items.
- Cantilever shelves: projecting cantilever structure, specifically for storing long or irregular materials (such as wood, steel pipes).
- Grid shelves: grid-like design, enhancing transparency and visibility.

6. Classification by Mobility

- Fixed shelves: fixed position, strong stability.
- Mobile shelves: can slide along the track, improving space utilization.
- Rotating shelves: achieve multi-angle access through rotation, saving aisle space.
- Combination shelves: modular design, flexible splicing to adapt to different layouts.

7. Classification by Height and Weight

- Low shelves: height below 5 meters.
- Medium shelves: height between 5 and 15 meters.
- High shelves: height exceeding 15 meters.
- Light shelves: load capacity ≤150 kg per layer.
- Medium shelves: load capacity 150-500 kg per layer.
- Heavy shelves: load capacity ≥500 kg per layer.

8. Classification by Access Method

- Manual access: such as partition shelves and shelf shelves, relying on manual operation.
- Mechanical access: beam shelves, drive-in shelves, shuttle shelves, etc., used with forklifts, shuttle cars, etc.

9. Classification by Application Scenarios

- Warehouse shelves: focus on space utilization and bulk storage, including beam shelves, drive-through shelves, gravity shelves, etc.
- Supermarket shelves: focus on display effect and customer convenience.
- Display shelves: used for product display in retail environments.

10. Special Function Types

- Mezzanine shelves: multi-layer platform structure, suitable for situations with limited space but requiring layered storage.
- Flow-through shelves: using inclined slides to achieve first-in, first-out of goods, often used for production line picking.
- Double-deep shelves: double-row parallel storage, improving storage density.
- Narrow aisle shelves: operate in narrow aisles with special forklifts, maximizing space efficiency.

These classification methods do not exist independently. In practical applications, they are often combined and selected according to warehouse conditions, cargo characteristics, and management needs. For example, automated automated warehouses may involve high-bay shelves, shuttle car systems, and enclosed structural designs.