If the threat of virus and malware is a factor in wanting a Mac over a PC this year, the iPad (with the Apple-approved apps from the App Store) is an even better investment.
Before pulling a trigger on an iPad, carefully consider getting one with cellular connectivity. Much of the iPad's popularity has everything to do with the portability factor; having cellular makes your iPad that much more capable, especially if you use the machine to go. As a bonus: the cellular models offer GPS, as well.
Pros: Instant on; slim chance of installing malware due to App Store policies; thousands of apps available for free and purchase; least amount of troubleshooting compared to other devices
Cons: Single-tasking interface; storage is fixed
Final tips: If you're a student, Apple gives education discounts of up to a couple of hundred dollars off when you show your student ID. There's also a promotion running until September 21st that gives up to $100 gift certificate on new iPad/Mac purchases that can be used in the iBooks store, the App Store, and the iTunes store. Even if you're not a student, you can take advantage of the Apple Refurbished store where you can purchase products with the same one year warranty as Apple's new machines, but at a pretty good discount. Refurbished computers are machines that have been fixed prior to being sold, but I have never had any issues with any of Apple's refurbished models.
Lastly, don't forget to utilize the resource called iTunes U, which is a free online depository teachers use to share lesson plans, courses, lectures, videos, and other learning materials to supplement your classes.
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