Google has introduced Priority Inbox, a new Gmail tool that aims to prioritize e-mails based on their importance. Gmail has always been pretty good at filtering junk mail into the “spam” folder.

But today, in addition to spam, people get a lot of mail that isn’t outright junk but isn’t very important—bologna, or “bacn.” So we’ve evolved Gmail’s filter to address this problem and extended it to not only classify outright spam, but also to help users separate this “bologna” from the important stuff. In a way, Priority Inbox is like your personal assistant, helping you focus on the messages that matter without requiring you to set up complex rules.

Priority Inbox splits your inbox into three sections: “Important and unread,” “Starred” and “Everything else”.

As messages come in, Gmail automatically flags some of them as important. Gmail uses a variety of signals to predict which messages are important, including the people you email most (if you email Bob a lot, a message from Bob is probably important) and which messages you open and reply to (these are likely more important than the ones you skip over). And as you use Gmail, it will get better at categorizing messages for you.

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A security report by Microsoft claims more than 97 percent of all e-mails are spam, and that the global ratio of infected PCs is around 8.6 for every 1,000 uninfected machines. Another observation is that hackers are increasingly targeting flaws in Office and PDF documents.

Paul Woods, a senior analyst at security firm Message Labs, is surprised by Microsoft’s findings. Woods says their own analysis shows that around 81 percent of all e-mail traffic is spam.

Microsoft said people should not panic about the high levels of unwanted e-mail.

Cliff Evans, head of security and privacy for Microsoft in the UK, told BBC News: “The good news is that the majority of that never hits your inbox although some will get through.”

Ed Gibson, chief cyber security advisor at Microsoft, said the rise in spam was due to traditional organised crime figures moving away from exploiting software vulnerabilities and “targeting the weak link that is you and me”.

“With higher capacity broadband and better OS (operating systems), and higher power computers it is easier now to send out billions of spams. Three or four years ago the capacity wasn’t there.”