Do you use an external drive or a flash drive to store some of your data? Then you might consider encrypting it. It's a bummer to lose a piece of equipment or have it stolen, but what'd take that from bummer to nightmare is knowing that someone may have access to, say, your private financial information.
Here's all you need to do to encrypt the drive and protect it with a password:
• Connect any external drive to the Mac
• Right-click on the external drives name in the Finder and choose "Encrypt DiskName…”
• Set and confirm a password, then set a reasonable password hint, followed by clicking the "Encrypt" button
Do not forget the password or you will lose access to the data on the drive!
• Wait while the encryption takes place
The encryption process can be very quick for smaller drives like USB keys and SD cards, but can take quite a while for large external hard drives used for backups or personal data. Be prepared to wait a bit for anything larger than a few GB in size, as the general encryption-to-GB time ratio seems to be about 1 GB per minute.
Once the drive has finished encrypting and is disconnected, a password will be required before the data can be accessed from the Mac. To maintain the password protection, be sure to uncheck saving the password to the Keychain when asked.
Did you know that OS X lets you rename a file directly from the application it's opened within? This feature is supported in most bundled Apple applications, including TextEdit, Pages, Preview, and others.
• Hover over the title bar
• Click the filename to pull down a menu, enter the new name and hit the return key to save the files name change
The file extension remains consistent with the files format, and unlike renaming things in the Finder you can't accidentally change the file extension too. The usual method of renaming files through Finder is still around, but if you're saving files directly to iCloud this is likely the preferential method.
The first scrolls you all the way to the bottom of the page you're on; the second puts you at the top. So if you need to move in either direction, you don't have to actually scroll at all. For those of you who use Chrome or Firefox, this works in those programs, too.
This little shortcut is good to remember, as you can use it in other places around the Mac. In document-creation apps (like Pages or TextEdit), those shortcuts mean "jump to the beginning or the end of the text". So you don't have to scroll in those programs, either.
Finally, if you add Shift to those shortcuts, it means "select all the text between where my cursor is and the beginning/end". So if you place your cursor in the middle of a document (or select some text on a webpage), Shift-Command–Up Arrow will select everything between your cursor and the beginning of the document; Shift-Command–Down Arrow will select things between there and the end. We use this as an alternative to click-and-drag to select text, and it's more controlled than Select All.
How many times have you typed something to discover the last two characters are in the wrong order? You know, when “the” turns into “teh” and “because” into “becuase”, a fairly common general mistype.
Apparently it happens often enough for there to be an individual keyboard shortcut to instantly swap the last two typed characters, and that keyboard shortcut is Control+T.
Starting with OS X Mountain Lion, your Mac could take dictation. But, just as with the dictation feature on iOS, the OS X incarnation required an Internet connection, couldn't show its progress while you spoke, and could only listen for about 30 seconds at a time. That all changes with a single checkbox in OS X Mavericks.
Open System Preferences and click on the Dictation & Speech pane. There, you'll find a checkbox for Use Enhanced Dictation. The first time you check it, you'll need to wait out a hefty (about 750 MB) download, but once you're done, you can dictate a lot more freely.
Now, transcription happens on your Mac (not Apple's servers), and you can see the transcription appear as you speak, in real-time. In fact, the cursor remains active too; if you see a mistake, you can click around (without speaking) to make your edits, put the cursor back where it needs to be, and start talking again.
OS X Mavericks also offer many speech-based editing tricks. While you cannot delete - if you say "delete that" OS X Mavericks types "delete that" - you can do quite a bit of other editing such as new line, new paragraph, plus tons of other symbols, spaces, capitalization and more. Here is Apple's KB article with a detailed list of dictation commands.