Spell checking is System Wide. While in a forum like this, just set Safari, the Web Browser, to "Check spelling as you type". Its under the Edit menu.
The new Macs can be either shut down or left on. This is a matter of personal choice and has been the subject of numerous posts, on both sides of the OS aisle. Your new Mac will go to sleep after a set amount of time and will quite happily sit there until you touch the keyboard or mouse. It's not quite like Hibernation but it is a very deep sleep. Drives shut down, screen goes off, etc.
A good surge protector is always a recommendation, personally I would go with a Battery Backup for the system. This will not only protect your computer from surges, it will allow it to be shut down nicely in the event of a power failure. By one big enough to power your machine for at least 10 minutes. Longer is better.
There is no key for shutting down programs all together, but once you have selected Shut Down from the menu, all the open programs will be closed, nicely, by the System. You will be prompted to save any unsaved documents.
It may be possible to renew AppleCare before the three year period is over. I would not try to extend it after the three years were up.
Don't get too embroiled in the reading. You will learn most of what you need to do just by playing with it.
How soon?
P
I downloaded all of Switch 101 and Mac 101 yesterday. Probably read too much at one time.
Re: Spell Checking. I read about TextEdit, and a little widget. But what was not answered for me was how spell checking can be used in these community forums. Does one just have to create a document, check the spelling, and cut and paste it here in the message body?
In "Tiger for Dummies" I read that a Mac is built to be always on except in case of a storm. Is this correct? It said there is a key for closing all programs before shutting down. As storms pop up unexpectedly in my area, is there a reliable surge protector for added safety?
Last question (for now
), can AppleCare be renewed when the 3 years are up? Seems I read something about that in this forum.
Thank you.
Angeline

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