To make a backup of your computer that is useful if your computer crashes you need to:

1.   1. Buy an external firewire hard drive
2.   2. Format the hard drive
3.   3. Download some backup software
4.   4. Backup your Hard Drive
5.   5. Run the backup software often

Now let me explain those steps in more detail.

2. 1. Buy an external firewire hard drive You need a firewire drive because even though macintosh has USB, you cannot start your computer from a USB drive in an emergency, you can only start it up from a firewire drive.
   You need one at least as big as the hard drive on the computer you are intending to back up. Eg if you have an 200G hard drive on your imac, you should get at least an 200G for your backups. This way you will always fit your backup on the external drive.
4. 2. Format the hard drive
   Plug in your new hard drive. Run Disk Utility (in your Applications/Utilities folder). Select your new Hard Drive in the left pane, and in the Erase tab check it says ‘Mac OS Extended (Journaled)’ as below, type in the name you would like to call it (eg Backup) (here it says Untitled) and press Erase. It will now erase and format your external Hard Drive ready for use and call it Backup. 

   

   If you have a large external drive, and you want to store other things on it apart from the backup, such as movies and pictures, then it is best to ‘partition’ it into two sections, one for your system backup, and one for files. To do this select the disk in the left pane and click on the partition tab. Select ‘2 partitions’ and adjust to the size you want. Again, name them, make sure they are both Mac OS Extended (Journaled) and press Partition. In the example below I have partitioned my hard drive into two, one for the backups (80G) and one for the rest.

   

6. 3. Download some backup software
   Go to http://www.shirt-pocket.com/SuperDuper/SuperDuperDescription.html and download the latest version of SuperSooper. It’s free to be able to do a basic backup, or you can pay if you want extra features such as incremental backup (it’s faster, but the end result is the same). Copy Superdooper to your macintosh applications folder.
8. 4. Backup your Hard Drive
   Select your Macintosh HD in the left menu, select your new firewire drive in the right one, select ‘backup – all files’. Press copy now, go and have a cup of coffee while you wait a long time for it to copy all your files, perhaps up to an hour or so. 

   

   It’s good to select ‘Repair permissions before copying in the options tab, see below. This makes sure your OS X is functioning well before you back it up, otherwise there can be some problems.

   

9. 5. Run the backup software often
   The most important thing about backing up is to do it regularly, I do it once a week. it’s good to do a backup before you install any new software – especially system modifications or large software, in case something goes wrong in the installation so you can go back to what it was when you backed up.

How do I use the backup in an emergency?

1. Go to System Preferences, select ‘Startup Disk’, select your external Backup, press Restart.
2. OR in a real emergency when you can’t boot onto your normal OS X…
3. Press Option-Command-Shift-Delete during startup. This will bypass the primary startup volume and seek a different startup volume such as the external one.
4. You are now running from your backup, and you just repeat the sections called Format the hard drive and Backup your Hard Drive but treat your Backup as the main one and the main one as your backup. In other words, run Disk Utility and erase your Macintosh HD, then run Superdooper and backup from your Backup to Macintosh HD. When the backup is finished, select Machintosh HD, and restart. You will now be running from your main computer again.
5. You might want to print these instructions out, so they are handy in an emergency. It’s no use having the instructions on how to boot in an emergency on your computer – you won’t be able to read them. Don’t laugh, I’ve done it!

   Stay tuned for an update on how to use time-machine. 

This Logitech presenter is great. After using the ATI remote wonder for a year or so, and a Microsoft cordless mouse also, I’ve done a bit of research, and came up with these little units as the as the best in my opinion. They are $79 at Officeworks and have all the features you need…

• a long range.
• works with keynote or powerpoint.
• the battery display indicates that the remaining battery life with little bars, so you’re not caught out with a flat battery. 
• the forward and back controls click, so you can feel that you have pressed them.
• if you have a time to end by, eg you are presenting to a group on a timetable, you can set up the timer, it gives you 5 min and 2 minute vibration warnings.
• It has volume up and down which automatically work on the mac with no setting up.
• the usb receiver stows away in the transmitter, and it all comes in a little padded pouch.
• it doesn’t need any drivers for Macintosh, it just works!

 Unfortunately, because it doesn’t need any drivers, you can’t program the keys to do what you want them to do, and the blank screen key doesn’t work. You can download the shareware program USB Overdrive to re-map the keys to do anything you want.   The side view shows volume buttons.  the ATI wonder remote is still better as a remote control for the DVD player  and itunes applications, as it has more buttons, but this Logitech unit is more reliable and simpler.

1. Go to your utilities folder.
   (Click on your desktop anywhere so that the finder is active.
   Hold down apple-shift-U, this will open your ‘utilities folder.)
2. Open ‘Activity Monitor’
3. Press apple-1 so that the main window of Utility Monitor is open.
4. Click on the ‘System Memory’ tab at the bottom of the window. This will display a little pie graph of how much memory you are currently using.

There are two important items to take note of ‘Free:’ and ‘Page ins/outs:’

Free tells you how much free memory you currently have, the higher the better, and
Page ins/outs tells you how many times your computer has had to slow down because it has run out of memory and needed to use the hard disk to ’switch’ some of it’s memory in our out of use. This really slows down your computer.

If the page in/out count is increasing as you watch it, this is not good, it means your computer has run out of free memory, and so temporarily is using the hard disk as memory. The faster the page in/out count is increasing, the worse the problem – your computer is struggling along and not performing as well as it could. You need more memory.

If you have had lots of free memory since the last time you restarted your machine, the Page ins/outs count will be 0/0. This means your computer had enough memory and has not run out. You dont’ need more memory.

It may be that your Pagein/outs count is high, something like 50431/10850, but steady and this and not increasing. What this means is that some time in the past when you opened a lot of programs, you ran out of memory, but now you have enough. Reboot, check the Pagein/outs count again. It should be 0/0. If it is not 0/0, have a look at it while you open a program or two and see how fast it increases, the faster, the worse your system performance will be.

Here is a screen shot of my computer. My page in/out count is quite high – 66825/697, but I still have 189 MB free, and the page in/out count is not increasing at the moment. This means that sometime since the last reboot, my computer ran out of memory, but currently it is OK. If I reboot the page in/out count will return to 0/0, and stay there unless I go crazy opening lots of programs. I don’t’ need more memory.

To quote from apple:
Moving data from physical memory to disk is called paging out (or swapping out); moving data from disk to physical memory is called paging in (or swapping in)… Extended periods of paging activity reduce performance significantly; such activity is sometimes called disk thrashing.

One more note: Under Leopard rather than giving a ‘count’ of page in/outs, it gives a size in MB of the amount of RAM that has been pages in or out – the numbers are smaller but the same principals apply.

In this article I described the fix for the G4 motherboard fault, but it seems from the comments that more models are affected than what I described there.

SYMPTOMS:

• After being on for a few minutes, your ibook gets a blank black screen, the fan turns on, and the computer freezes.
• You can’t do anything at all except power down the computer by holding the power button.
• You restart and it doesn’t boot up.
• You squeeze the bottom of the computer tightly together just to the left of the trackpad, and it boots up.
• It tends to boot up when it is cold, but then stops working when it warms up.

Still unsure? Read more about the symptoms here and here.

Here are the results of a survey regarding the affected models:

With so many different battery types, how do you know whether to recharge them or flatten them every time you use them, and does it matter?

It does matter. Some batteries can be damaged if you use them wrongly, others have a reduced life. Here’s a quick guide.

• Lithium Ion Batteries (Li-ion) are found in all new Apple laptops and ipods. They are also in digital cameras and mobile phones. The more you keep them charged the better. It’s best to never let them run out. They only last about 300 full discharges, so if you let them run totally flat you have used 1/300th of their life. It’s best to charge them as often as you can. Whenever you are not using them put them on the charger. Keep them cool while charging.
• NiCad batteries are exactly the opposite. It is best to let them run totally flat each time you use them. They are found in older cordless drills, older laptops and some cordless phones. If you recharge them before they are fully flat they will ‘remember’ where you discharged them to. So if you keep charging them when they are half empty, you’ll find they will stop working when they are half empty.
• NiMH batteries are like Nicad batteries but the ‘memory’ effect is not as bad. You should still discharge them fully but it won’t hurt them quite as much if you don’t. If you cant’ do it every time, try to fully flatten them occasionally.
• Car batteries (lead acid batteries – also in some camcorders) are the worst for being damaged when fully flat. Every time they go fully flat it does irreversible damage – 3 or 4 times and they will be totally wrecked. Like a lithium ion battery, it’s best to keep them as charged as fully you can.

I purchased mine from RIHAC in Melbourne, Australia. They have a good unit, with good instructions as well as good phone support, the sell the CIS system for about $150 and it comes with I think it was 100ml of ink per color. Installing the CIS system is about the same complexity as changing a pushbike tyre, or sewing a button on a shirt. If you can follow instructions, you should be able to install it OK. Mine’s been going about a month with no problems at all.