The rules of Computing (how to keep your data)

Schofield’s Laws of computing


Schofield’s laws of computing are about your data. Your data is often a record of your life and your family’s life and is worth far more to you than any computer.

Schofield’s First Law of Computing states that you should never put data into a program unless you can see exactly how to get it out.

Make sure you know how to get at your old photos and other data stored on old devices. When you get a new computer or phone, make sure your move your data. Beware of obsolescence. If your family archives are stored on floppy disks, or even DVDs, you may struggle to access them. Be prepared to migrated your archives when you buy a new computer.


Schofield’s Second Law of Computing states that data doesn’t really exist unless you have at least two copies of it.

Always back up your data. It is so easy to lose a precious archive, either by deleting it accidentally, or by equipment failure. Data backup can also include a cloud solution.

If you upload everything to a cloud provider (GDrive, One Drive, iDrive etc.) make sure that you do keep a copy of your data in the real world, and that you back up your data regularly.

Schofield’s Third Law of Computing states that the easier it is for you to access your data, the easier it is for someone else to access your data.

Obviously, military grade security may be over the top for a computer that only you use but bear in mind that a list of passwords can be extracted from some computers, especially older machines.

Remembering passwords is a pain. If necessary, make a note of the key passwords in a book (not on a yellow post-it note stuck to the computer screen) and store safely (perhaps in a safe). Online thieves are not going to find your notebook hidden behind the cookery books. This is especially important if you are using encrypted storage, for your password is the encryption key. Loose this and you will not be able to access your data.

Jack Schofield was the editor of the Guardian computer column, Ask Jack and wrote extensively about computer issues for several years. Sadly, Jack died in March 2020, but his voice lives on in his work which can still be accessed: Ask Jack | Technology | The Guardian