Almost an exact replica of the Puffin book, written by John Astrop, with the same title. It is a database enabling the user to store secret information. With two secret codes to crack no-one can sneak a look at your own file.
After the program has loaded, you are asked if you wish to load previously saved data. If you do, you can load it, update, and then resave it. It's that simple. On the other hand, if you want to start a new file, before you have filled the previous one, about 400 or 500 entries have to be made. The file doesn't have to be filled before it can be saved, though. There are fifty pages to choose from, including My Vital Statistics, and Pocket Money, which shows to whom it is aimed.
The complete package includes book, cassette and full instructions. I loved being secretive when I was a child, and if you do, or indeed your child does, then I think this program would get a lot of use in your household.