What is Encryption?

Encryption is the practice of encoding and decoding data. When data is encrypted, it means that an algorithm has been applied to encode the data so that it is no longer in its original form and therefore can't be read. The data can only be decoded back to its original form by applying a specific decryption key. Encoding techniques are an important part of data security, as they secure sensitive information from threats that include exploitation by malware and unauthorized access by third parties. Data encryption is a versatile security solution: It can be applied to a piece of data such as a password, or more broadly across data in a file, or even across all data contained in storage media.

How Encrypting Data Protects Computer Users

You will typically encounter data encryption when you are asked to enter personal identifying information into a Web form. Financial, government, school and shopping sites usually encrypt your data to help protect against theft and fraud. You should always verify that Web forms are secure and that your data will be encrypted by looking for the following:

The web page URL begins with ""https"": This indicates that your data will be encrypted and transferred using a secure protocol.
A lock-shaped icon, usually on the lower left or lower right of the browser screen. When you click on the lock icon, you will be able to see the security details for the site.

Just as you would expect sensitive data that you enter into a third-party website to be encrypted and secured, data on your home computer also needs to be protected. Files, passwords, emails and data backups should be encrypted so they are safe from hackers and thieves — versatile security solutions are available to encrypt and store sensitive information.