Back in October 2013, after a string of leaks by Edward Snowden pushed major internet companies to do more with regards to user privacy, Yahoo announced that it will add automatic encryption to Yahoo Mail by early 2014. This means that all emails will automatically be encrypted by the email service. The company has formally announced that it has delivered on its promise. It is now automatically encrypting all connections between its users and Yahoo Mail.
What this means is that anytime anyone uses Yahoo Mail, through web or mobile apps, IMAP, POP, SMTP or mobile web, it will be 100 percent encrypted by default with 2,048 bit certificates. Not only that, this encryption also extends to attachments, contacts, calendar and messenger apart from all emails in Yahoo Mail. The company says that security is a key focus for it and that it will continue to enhance its security technology. Yahoo not only pledged to encrypt its mail service, it also promised to encrypt all data flowing to and from its servers by April 2014. Its about time that Yahoo added this security feature to its email service, rivals Gmail and Outlook have offered it since 2010 and 2012 respectively. Not sure who it would protect you against the NSA though, it is allegedly capable of cracking almost all kinds of encryption.