Pod: A general term for an MP3 player. It could be an iPod, a cell phone or some other kind of MP3 playing device.

Podagogy (podcasting+ pedagogy): Podagogy is the art or science of using Podcasts for educational purposes (taken from: http://www.le.ac.uk/impala/projects/Podagogy.html)

Podagogy is the pedagogy for podcasting. It represents the power of the spoken word because it appeals to auditory learners, it can be listened to anytime, anyplace, it fosters mobile learning (m-learning), captures the instructor?s enthusiasm, can be listened to multiple times for review, bring in guest lectures, debates, virtual field trips, etc. It can also be used in Student presentations since they can create their own digital files (taken from: PowerPoint presentation on podcasting by Burks Oakley of the University of Illinois)

Podcast: A podcast is a series of digital media files (either audio or video) that are released episodically and downloaded through web syndication. The mode of delivery differentiates podcasts from other ways of accessing media files over the Internet, such as simple download or streamed webcasts: special client software applications known as pod catchers (e.g., iTunes, Zune, Juice, and Win amp) are used to automatically identify and download new files in a series when they are released, by accessing a centrally-maintained web feed that lists all files associated with the series. New files are thus downloaded automatically and stored locally on the user’s computer or other device for offline use, giving simpler access to episodic content.[1][2] – Wikipedia

Podcaster: A podcaster is a podcast host. It corresponds to a radio host or TV anchor. This expression is used by some about receiving podcasts.  A podcatcher (also called a podcatching client or a podcast client) is a specialised type of news reader designed to capture podcasts on the Net and store them on your hard drive and/or portable media player for future playback.

from http://www.ausmall.com.au/freesoft/podcatchers.php

Podcatcher/podcatching software: A podcasting client. Software in a user’s machine that downloads and aggregates podcasts for synchronization to a digital music player.

from http://www.techweb.com/encyclopedia/defineterm.jhtml?term=podcatcher

Pull and Push technology: Push technology, or server push, describes a style of Internet-based communication where the request for a given transaction is initiated by the publisher or central server. It is contrasted with pull technology, where the request for the transmission of information is initiated by the receiver or client.

from  http://en.wikipedia.org/wiki/Push_technology

Pull technology is used when surfing the WWW to seek out and download information. This contrasts with push technology, where data is automatically delivered to your computer.

from  http://www.learnthenet.com/english/glossary/push.htm