Basically, there are two types of interpreting:
1) Consecutive interpreting,
2) Simultaneous interpreting.
Typical characteristics of a consecutive interpreter are an excellent short-term memory, good presentation, and power of persuasion. In consecutive interpreting, the speaker first gives a rounded statement (in the source language) that can take up to 15 minutes, and the interpreter simultaneously takes notes. After the speaker has expressed his or her thought, the interpreter renders what has just been said in the target language. For his or her rendition, the interpreter is supposed to use only as much time as the speaker did. The speaker waits until the interpreter finishes and then continues with his or her speech.
Consecutive interpreting is used, for example, at negotiations, in hospitals and courts, and over the phone.
A simultaneous interpreter works in a special booth and listens to the speaker through earphones. In general, the interpreter can also see the speaker through the window of the booth. As the speaker delivers his or her speech, the interpreter simultaneously renders the speech in the target language, i.e. he or she interprets simultaneously. There is, however, a short time lag between the statement of the speaker and that of the interpreter. There are usually two interpreters in a booth. The interpreters take turns every 30 minutes. It is extremely important for a simultaneous interpreter to speak clearly and to be able to process ideas and statements quickly.
Simultaneous interpreting is used at conferences; therefore, it is often referred to as conference interpreting.
See also Translating.