Email is NOT an inherently secure method of communication. Although most of the popular webmail providers now utilize HTTPS connections by default, that still doesn’t mean that your provider does not have access to your message’s contents.
Since most of us now access email through web clients, it would be beneficial to have a way to utilize the convenience of a webmail account, while having the assurance that our correspondence was more secure. If you are a Gmail user, you can try the previously covered SafeGmail, but what if you use another webmail provider?
Mailvelope might be a viable option.
Mailvelope is an extension for Chrome and Firefox that offers free, OpenPGP encryption for many popular webmail providers, including Gmail/Google Apps, Outlook, and Yahoo!. Once installed, you generate your own public/private key pair within the extension’s preferences. After key generation is complete, you will now see a lock icon in the compose window of your webmail provider. Click it to encrypt the contents of your message.
Once your receive an encrypted message, the process will work in reverse. Simply click the lock icon, again, to initiate decryption and enter your password. The Mailvelope service will search your keys to find the appropriate match and decrypt your message.