Printing from iPhone

what do I need to do to print from my iPhone

Very little. Apple describes here how iPhones print wirelessly using AirPrint.

AirPrint is described on that page: AirPrint is an Apple technology that helps you create full-quality printed output without the need to download or install drivers.

Hi,

First of all, study the list in the AirPrint article mentioned by David McKinlay. If your printer model is there, all is well. The iPhone and the printer must be connected to the same network (Wi-Fi router).

Without an AirPrint model, it may be possible to print from an iPhone, but only if the printer manufacturer has a special iOS app with support for the printer model in question.

A USB printer, could be connected to a Mac (which would act as a print server). In this case, a special app (Printopia is one example) would be used on the computer instead.

If you need additional information, please post back with your exact printer make and model.

No download required; the linked AirPrint document advises that AirPrint is built in to most popular printer models and it is this to which the iPhone connects over wi-fi to print without drivers. If the printer is not equipped with AirPrint the iPhone cannot print to it. As you may have seen, the list of printers with AirPrint is rather long.

And you're very welcome, from Melbourne, Australia