Unencrypted data can be accessed by anyone at any time. Encryption technology locks it up so that it can only be viewed by the person that has the encryption key. Whether you’re using symmetric key encryption, where the same key encrypts and decrypts, or dual-key asymmetrical encryption, where you need two different keys, either technology brings similar benefits. Given that desktop computers can execute billions of operations every second, the performance hit that most applications take from using encryption is still well worth it for the many benefits that it brings.
The Secure Sockets Layer / Transport Layer Security system that drives secure web connections is one of many uses of encryption to provide private communications. SSL and other protocols encrypt file transfers, downloads, and audio and video calls. You can also create an encrypted tunnel, called a Virtual Private Network, to let you log in to a separate private network like a corporate intranet.
Protect Stored Data
Encryption also protects data that you store on your computer, much like putting a lock on a file cabinet. When you encrypt some or all of your hard drive or thumb drive, you prevent people who may turn on your computer from accessing files without your permission. You also protect those files from being viewed in the event that you lose your drive or have it stolen.
Data Integrity Checks
One side benefit of encryption is that small changes can render the entire document useless. If someone changed a word in this article, you might not notice it. When an encrypted file gets changed, though, you probably will not be able to decrypt it. This makes it clear when a file has been changed, tampered with or corrupted.
Easy Data Destruction
Another side benefit of using encryption when you store files is that it makes it very easy for you to effectively destroy files. Instead of having to delete the file and overwrite it, you can just delete the key and overwrite that small space on the drive. Deleting the key renders the file completely unreadable. Some solid-state devices actually use encryption for precisely this purpose — to make it easier to bulk-erase the drive.