You plug stuff into them. It's really not difficult.
Almost any USB wireless adapter, and depending on model you can use also PCI mini cards.
That's a slower computer, so one with a slower burning speed might be better. Also, if there aren't any USB ports onboard, be ready for superslow burns.
Technically, yes. The ThinkPad 765D has two CardBus slots, which can be used to install a USB hub. However, the cost of doing so, the likelihood that you would need to upgrade your operating system anyway (only certain versions of Windows 95 supported USB), and the age of the laptop for doing anything actually useful make it an impractical upgrade.
You can find out by running diagnostic software on your system. Sandra sisoft is excellent an easily found on the Internet!
This Panasonic Toughbook has 3 USB ports.
iPads do have usb ports. You just have to buy an adapter
There is no minimum or required number for USB ports on a laptop. Depending on the age and design of the laptop, it could be anywhere from zero to ten. I have seen only 2 USB ports on older laptops, most of the new ones atleast have 4 USB ports. Netbooks(10" & 11") have not more than 2 USB ports. If in anycase you need more USB ports, you could buy an USB hub for as less as 10$, which will add 4 more ports to your laptop.
Who told you it had no USB ports? Of course it has USB ports. The iMac has 4 USB ports, 1 Firewire port, 1 Thunderbolt port (2 on the 27" iMac), 1 Ethernet port.
Any compatible USB or Serial external CD-ROM drive should do good justice. If your ThinkPad supports SCSI interface and has a SCSI connector you can get a SCSI external drive. I would recommend Sony or Creative CD-ROM drive.
NoYou can open the computer up and remove the USB ports.
The Atom N270 laptop has three USB 2.0 ports.
A USB hub can be attached to any of the existing USB ports to provide additional connectors.