--The first Macs to offer USB were introduced in 1998. The first Ipods were introduced in 2001.--
Incorrect. The first was the 2001 USB ibook. That is why they used the USB in the name because it was the first one.
Are you saying the first Mac with USB was the 2001 iBook?
They were the iMacs, detailed here. And yes, they had (two) USB ports.
No, they called it the "Dual USB" iBook because it was the first iBook with two of them.
First iBook introduced in 1999 had a single 1.1 USB port. The 2001 iBook was referred to as the 'duel USB' model because it was the first iBook with two USB ports.
...actually no.
the PowerMac G3 Blue and White behind me has USB ports (was released in 1999...
You're wrong,
That is why they used the USB in the name because it was the first one.
Wrong again. Apple called it the iBook, period. It's sometimes described as the DUAL USB iBook to distinguish it from the earlier models, which had only one.