Don't use all upper case: This is commonly regarded as shouting, so don't be surprised if people think you've sent them an angry message.

Use line spaces. Long email messages in a single paragraph are not easy to follow so break it up to keep your readers attention.

Don't over-reply: Resist the urge to over-reply. Endless cc's are annoying and clutter your in-box.

Use clear subject lines, and keep e-mails short: A clear subject will help people decide whether to read the e-mail now or later. And a message that is succinct saves people time. We're all busy. Your correspondent will appreciate your thoughtfulness.  

Don't give away everyone's e-mail address: People may not appreciate being copied on mass e-mails that give other recipients access to their e-mail address. Use the bcc (blind carbon copy) feature to keep recipients addresses private.

Remember the "Rule of Three": If it takes more than three e-mail exchanges to sort out an issue, it's better to call.

What are some of the most annoying email habits?

Clicking "send" too fast: Re-reading every e-mail before you send it will help you catch typos, spelling errors and missing words. Spell checkers don't catch everything. People will judge you subconsciously on mistakes, especially in a business setting.

Unnecessary copying and forwarding: Copying the boss on every e-mail you send could take you out of his or her good graces, and sending along chain e-mails and jokes clutters people's in-boxes and leads to instant aggravation, especially if you're forwarding an attachment that could potentially infect someone's computer with viruses or spyware.

Getting in the last word: Again, the "Rule of Three" of applies: Avoid responding to e-mails with "Thank You" or other one word phrases. It clutters people's already full inboxes. If you really need to say something, just pick up the phone.

E-mailing on the go: Some people call it multitasking, but firing off e-mails from your BlackBerry or similar device during a business meeting, dinner with the family, or in the car while driving is rude. It sends the message that you've tuned out and are not engaged in the matter at hand.

Other common email mistakes:

• Forgetting the attachment

• Sending to the wrong person

• Using only one e-mail address