But how can we keep misunderstandings to a minimum?
Context is key. When you compose an email or tweet, the recipient can't see your face or hear the tone and inflection of your voice. They must rely on your words alone to guide them in interpreting what you're trying to say. If the recipient knows you well, they may be able to infer meaning more easily, based on previous interactions, but even then, misunderstandings can occur.
To minimize miscommunication, keep your writing concise. Stick with the facts, and move on. Use humor cautiously, particularly dry humor that may be seen as being flip, curt, or rude. Save the jokes for face-to-face situations, when your body language and vocal inflections can help in interpreting your words. And try to craft questions that cannot be accidentally read and interpreted in a different way than you intended.
A humorous example of this occurred around the turn of the last century. William Randolph Hearst made a bid to purchase a competing newspaper. He asked his rival for a selling price, to which the man replied, "Three cents daily. Five cents Sunday." Obviously, the rival knew what Hearst meant by his question -- and by answering the way he did, basically let Hearst know the paper was not for sale -- but this does go to show that the same question can have more than one meaning if interpreted differently.
Of course, it's not just what you say that matters; it's how you say it. When communicating in writing, it's important to know the subtleties of the medium you're using. For example, most people now know that writing an email or Facebook post in all caps is often equated with yelling. For a medium like Twitter, with its 140 character limit, the challenge often comes in trying to say too much in such a confined space. When composing a tweet, it's easy to inadvertently gloss over some of the details, in an effort to save space. Make sure you're not losing meaning -- or raising confusion -- for brevity's sake. If you can't adequately say what you need to say in the space provided, choose a different medium.