There are many technologies that can be used to support distance education and training. Some are used as supplements to traditional classroom environments; others are used as complete replacements for traditional lecture-based courses. While each technology might be better suited for one type of environment than another, it is important to consider its relative advantages and disadvantages. For example, some of them provide almost no interaction or communication between the learner and the instructor, or between learners. Some technologies provide limited contextual information besides the lecture material, while others provide the interested learner with a wealth of additional information. Consistent with chapter two, we must also note that some technologies allow for more flexibility by providing asynchronous support for learning, allowing learners to work at their own pace, while others are limited to a synchronous learning environment that also provides more communication possibilities. This chapter presents an overview of the various technologies that are being used in distance and distributed learning.