What are sound bites? How does their use influence the nature of the news?

What will be an ideal response?

An ideal response will:
1, Define a sound bite as a product of changing technology whereby the media are able to, for instance, take a small, 10-second section of a speech and use it instead of the substance of a candidate's position.
2, Discuss how sound bites could be beneficial in their ability to encapsulate complex subjects in short, digestible bits for citizens, but also how they might be negative in making peripheral aspects of the speech into the news, as noted by Jimmy Carter, or in allowing politicians to develop slogans over policy, as noted by Walter Cronkite.