USB
4 usb, with what each one actually specifies.
| Name | Millimetres | Inches | Notes |
|---|---|---|---|
| USB-C connector | 8.34 × 2.56 mm | 0.33 × 0.10 | A connector, not a speed — 8.34 × 2.56 mm, reversible. |
| USB 3.x | 5, 10 or 20 Gbit/s depending on generation | — | 5 Gbit/s originally, renamed repeatedly — check the speed, not the name. |
| USB 2.0 | 480 Mbit/s, 2.5 W (500 mA at 5 V) | — | 480 Mbit/s. Still what most cables and keyboards use. |
| USB4 | 20, 40 or 80 Gbit/s; USB-C connector only | — | 40 Gbit/s typical, built on the Thunderbolt 3 protocol. |
- USB-C connector size A connector, not a speed — 8.34 × 2.56 mm, reversible.
- USB 3.x size 5 Gbit/s originally, renamed repeatedly — check the speed, not the name.
- USB 2.0 size 480 Mbit/s. Still what most cables and keyboards use.
- USB4 size 40 Gbit/s typical, built on the Thunderbolt 3 protocol.