Those of you who have read my past columns know that I consider backing up important data an essential task for all computer owners.

I've also told you about the various backup techniques that you can use. Today I'd like to give you a little more information about a backup methodology called "online backup."

Online backup is one of the easiest ways to back up, because you don't have to think about it. Since the backup is done over the Internet, you will need to have a broadband connection. After you sign up with a reputable online company, your files are backed up automatically to one of its servers.

Every time you change, add, or delete a file, the backup is also changed. You don't have to do a thing. You can think of this type of backup as an insurance policy that gives you peace of mind. After you pay for it, you don't have to think about it unless you have a catastrophic event. Then you simply cash in on your insurance policy, or in this case, restore your files from the backup servers to your computer.

Many companies provide online backup. However, this is a good time to stick with a trusted name. At the current time, there are only two companies that I have investigated and that offer me enough confidence to recommend them. They are Carbonite (www.carbonite.com) and Mozy (www.mozy.com).

I have been using Carbonite for my own data, and I have interviewed David Friend, the president of Carbonite, on my podcast, so I can highly recommend the company. Carbonite can be used for Windows XP and Windows Vista. A Mac version is due soon.

There are many things that I like about Carbonite. One is that it offers a 15-day free trial with no credit card necessary. So you can back up some of your files and even try to restore them to test the program and see how it works.

The second thing that I like about Carbonite is that it is easy. It has spent a lot of time developing a clear and clean interface that is extremely easy to use. Every step of the backup process is explained in plain English.

Here's a brief overview of how Carbonite works. You will find that Mozy and most other online backup programs work in a similar manner, although the details such as amounts of data, prices, and interface will be different.

With Carbonite, the default backup will choose all the files that it thinks are important, including e-mail, data files from applications such as Quicken, as well as your personal documents and photos. You can then add any other files that you feel you want to backup.

Once the backup begins, it runs in the background and doesn't interfere with your using your computer. If you have a lot of data, the initial backup can take a day or even several days.

It is best to leave your computer on during this time so that the backup can be accomplished as quickly as possible. After that, every time you change or add a document to the desktop or a folder that is marked for backup, it will be backed up. This is done quickly while you are working on other things.

The beauty of online backup is that you don't have to think about it. You don't have to do anything. Everything is backed up as you go. Carbonite has no limit on the amount of data that can be backed up, so you can back up as much as you like.

Carbonite puts a small colored circle in front of any file to show that it is already backed up or is in the process of backing up. So you can always see at a glance that the backup is working properly and if the file in question has been chosen to be backed up. You can right-click on any file or folder in Windows Explorer or My Computer to add it to or remove it from you backup.

Carbonite encrypts your documents as they leave your computer and stores them on encrypted servers, so you don't have to worry about having your data vulnerable at any time during the backup process.

Carbonite has proven itself to be a company that you can have confidence in. As of the beginning of the year, it was storing more than 3.1 billion files on 2.7 petabytes of disk. It receives more that 30 million new files every day. Their service is also trusted enough to be the built-in backup service used by Microsoft Money.

If you ever have a hard drive crash or a problem with your data, it is easy to restore any or all files. Carbonite also keeps several versions of every file, so if you happen to need a version that you previously created but have overwritten, you can usually retrieve just what you need. You can restore one or two files. If your computer crashes or is stolen, you can retrieve all your data to another computer.

The only downside to this type of backup is that if you need to restore everything and you have a lot of data, the restoration can take a day or more to complete. That makes this method unsuitable as the only backup for a business that needs to get up and running quickly. However, it is usually perfect for a home user.

Even if you have to replace your hard drive, you can quickly restore your e-mail, financial data, and files that you may need immediately, while the program slowly restores your photos and other documents that you don't need right away.

Carbonite charges $49.95 a year or $89.95 for two years, if you prepay.

If you are lackadaisical about backing up, compare that cost to the amount you pay for your home or car insurance, and consider it a cheap insurance policy.

Sandy Berger welcomes all of your questions and comments on today's column. Please post them on the Compu-Kiss Message Board at www/compukiss.com/happycomputing.