You will need a wireless router for your iPad. You would connect the router to your Internet source (cable modem, DSL modem, whatever) and for your desktop you could use wireless, but you would probably get faster speeds connecting the computer directly to the router with an Ethernet cable. Good wireless routers are US$20-50, i.e., cheap. I like Netgear routers, but there probably aren't any bad brands anymore. You will need to set up the router for best security, which is somewhat tedious but not difficult. Most routers use a configuration web page that runs in your desktop's browser, and steps you through the process.
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