Axis 1: the connectors
- USB-A: the rectangular legacy plug. Host-side for two decades; on chargers it is the compatibility port (QC-class power). See USB-C vs USB-A.
- USB-C: the reversible oval plug. Carries PD, PPS and up to 240W in the extended spec; the only connector for new charger programs.
- Micro-B: the pre-C device plug, still found on accessories and older peripherals; a declining but non-zero installed base for cable assortments.
Axis 2: the wiring inside
A USB-C cable may be wired for USB 2.0 (480 Mbps) or for USB 3.x / USB4 speeds, with or without video alternate modes. Charging cables are usually USB 2.0 inside - legitimately, since data is not their job - but a buyer who assumes a C plug means fast data will stock the wrong cable. State the data requirement explicitly, or accept USB 2.0 as the default.
Axis 3: the power rating
Independent of both axes above: 3A (60W class) or 5A (100W class, e-Marker identified). Full treatment in USB-C to USB-C cables. A complete cable specification names all three axes - for example “C-to-C, USB 2.0, 5A e-Marker, 1 m, braided” - and this site's cable guide turns that into a purchase-order template.