Erasure of digital information

Your computer is erasing things all the time, which could include pictures you saw on a Web site but did not save.

Security suggestions

• Use the iOS (iPads and iPhones), which is at present (2017) safer than Windows and Android devices. Each iPhone requires a 6-digit code every time it awakens, and freezes if the wrong number is entered 10 times. No software is available that can unlock a locked iPhone or iPad. (A member of "New York's Finest" (police) said to a reporter that "we've got á boxful of them" (iPhones and iPads).

Apple has argued successfully that a search warrant can not require them to write software that does not exist, to unlock these phones. Since it is committed to privacy, Apple has stated that future version of iOS will include encryption which they could not unlock even if they wanted to.

Turn off the automatic backup to iCloud in Settings, and anything else that is receiving backups, like Dropbox. For files that you dn't want anyone to see, use one of the many free and paid encryption programs in the App Store. Any program that implements Pretty Good Privacy (see http://en.wikipedia.org/wikí/Pretty good privacy) is OK. Note that in the US, police investigators (but probably not an ordinary policeman) know that an additional calculator, which works, might be hiding encrypted files, but that alone does mot constitute "probable cause" necessary for a search warran in the U.S. If all your files (you know which ones) are securely encrypted, you can turn the backup back on, which is very convenient and good protection against, say, your device being ruined by floodwaters.

• On Windows systems, use a inexpensive memory stick that connects to your USB port. Don't just use it for storage, install the browser and (even better) the operating system on the stick. Your computer will see it as drive D: or E:; booting off another disc instead of C: is an easy step in the bootup process. Any domputer geek will know exactly what I'm talling about, it is commonly done.

• • Do not leave the memory stick in the computer! That blows your cover. Hide it away each time, some place not near your computer.

• Don't have anything you wouldn't want law enforcement to see on your computer.

• Security is never perfect.

• Whether you can be forced to reveal a password is unresolved in the United States. But a judge can hold you in contempt of court and send you to jail until you comply with the judge's order. This has not heen effective because the consequences of revealing the code probably would leave him is a worse situation than being in jail. This has also happened with reporters, to protect their sources.