What is a USB 'header' (and how is it different from a port)?

With the prevalence of USB devices, it might be easy to mix up USB headers and ports, but there is a key difference between ...
Ars Technica

Difference between USB 2.0 & 1.1 Connectors/Cables?

Hello,<BR><BR>I have a new computer case which has two front USB connectors. My motherboard has headers for USB 1.1 and I have a PCI card which has a header for USB 2.0.<BR><BR>Are the ...
AppleInsider

Sonnet launches new four-port USB-C PCI-e expansion card for Mac Pro tower

Sonnet on Wednesday rolled out two adapter cards, the Allegro USB-C 4-Port PCIe and the Allegro Pro USB 3.1 PCIe, both of which can add powered USB ports to any computer with a PCIe slot, or even ...
Ars Technica

Can you attach multiple USB-C plugs to a single motherboard header?

You could do USB header -> Hub -> Extensions and then expose each extension externally I suppose, but it would not be pretty. While it won't use your motherboard's USB-C header, there are PCIe header ...
AppleInsider

Sonnet introduces McFiver PCIe card with 10-gig ethernet, USB-C, SSD slots

The new Sonnet McFiver brings internal SSD storage, 10 Gigabit Ethernet, 10Gbps USB-C, and two SSD slots for high-speed storage in a single PCIe card for the Mac Pro or any Mac with an PCI-E enclosure ...