Last time, we looked at the difference between synchronous and asynchronous communication media. This time, we'll look at using those styles. An important point is that if you mix-up one situation with the other method, you will get odd communication breakdowns. For instance, when you need to know something right now, don't send an email. Make a phone call. Not only are you going to get a better result, you're communicating your urgency to the other person through the style of communication. Likewise, if you need to let someone know something for reference, send an email, don't call. If you were to call to leave some reference information, the other party would be confused. They would feel like you had used the wrong medium. It's also interesting to note that it's relatively easy to replace forms of communication within one style. The best example is emails and voicemails. They are used almost interchangeably. Both offer a way to communicate information that doesn't require the presence of the other person. These forms are not perfectly interchangeable, of course. Each asynchronous medium has its own rules. Each implies its own level of asynchronicity: the amount of time that can elapse without response. Some are infinite: newsletters. Some are short: voice mails. And within each synchronous medium is a further level of synchonicity. A phone call has high synchronicity: you are required to drop most of whatever else you're doing to talk (effectively and safely!) on the phone. With instant messages, you don't have to pay rapt attention to be communicative. Any time you move within the medium, you have to be sensitive to the changing communications landscape.