Mac hints and tips
Get more memory - close widgets (10.4/5)
Hit the F12 key and Dashboard displays a collection of useful mini applications called widgets. Although they can be quite useful at times and some of them are excellent, you should be aware that they consume memory. After all, they are simply programs and all programs require some memory to run in.
Of course, his won't bother you if you have 2Gb of RAM installed in your Mac, but it can be a significant amount if you have 1Gb, and if you have just 512Mb then widgets should be completely avoided because OS X will be desperately short of memory and you need to reduce its requirements to a minimum or the Mac will slow to a crawl with lots of disk thrashing.
To see the effect that widgets have on the amount of memory that is free, go to the Utilities folder and run Activity Monitor. Select the System Memory tab in the lower half and look at the Free value. Now press the F12 key to invoke the Dashboard and display the widgets.
Click the plus button in the bottom left corner and start adding widgets. Add them all and then look at the amount of free memory - you can still see running Activity Monitor underneath, although you might have to move the widgets around so you can still it. Now close all the widgets and watch the free memory rise.
With no widgets open then no memory is used and the first one that is run causes the Dashboard client to start, which uses 11Mb of memory. From then on, each widget increases the amount of memory used and leaves less for your applications. It's possible to lose 50 or 60Mb of memory with lots of widgets in use and if you don't have much in your Mac, it can make a significant difference to the performance. Close all your widgets and don't use them unless you have to or unless you have 2Gb of memory.
Some files are actually folders (10.4/5)
Some of the files you see in Finder windows aren't actually files and they are really folders. Normally, you won't notice the difference, but in some circumstances you will and you might be confused when you see a folder instead of the expected file.
To see how Finder handles files and folders and can make them appear to be identical, start TextEdit and type in a few words of text. Save the document as a standard RTF file. Now select Save As and choose RTF with Attachments (RTFD) in the File Format pop-up menu. Quit TextEdit and Control+click each file - you'll see two different menus because one is a file and the other is a folder - OS X calls it a package. With the RTFD file there is a Show Package Contents menu option. Select it and the RTFD file is shown to be a folder that contains the text in an RTF file.
The reason for using a folder instead of the file is so that if you insert multimedia elements in the text file, such as pictures, they can be stored in the RTFD folder along with the text file. Links in the text file refer to these elements, so don't muck around with the contents or you won't be able to load the file again.
Normally, you don't need to worry about files that are really folders and you just leave it to OS X to figure out how to handle them. It's convenient to treat folders as files under certain circumstances, such as with TextEdit files, Pages documents, applications and so on. However, their true nature will be exposed if you use another operating system. For example, copy the RTFD file to a USB flash memory drive and then insert it into a Windows PC and you'll see a folder. If you use an online storage facility you might also see your 'files' as folders too because the servers use Windows or Linux operating systems.