A podcast is a digital media file, or a series of such files, that is distributed over the Internet using syndication feeds for playback on portable media players and personal computers . A podcast is a specific type of webcast which, like ' radio ', can mean either the content itself or the method by which it is syndicated; the latter is also termed podcasting .
The host or author of a podcast is often called a podcaster . The term "podcast" is a portmanteau of the name of Apple 's portable music player, the iPod , and broadcast  ; a "pod" refers to the iPod, and "cast" to the idea of broadcasting . Specifically, Podcast means, Portable OnDemand broadCAST.
In other words, a podcast is a collection of files (usually audio but may include video) residing at a unique web feed address. People can "subscribe" to this feed by submitting the feed address to an aggregator (like iTunes - software that runs on the consumer's computer).
When new "episodes" become available in the podcast they will be automatically downloaded to that user's computer. Unlike radio or streaming content on the web, podcasts are not real-time. The material is pre-recorded and users can check out the material at their leisure, offline.
Though podcasters' web sites may also offer direct download or streaming of their content, a podcast is distinguished from other digital media formats by its ability to be syndicated, subscribed to, and downloaded automatically, using an aggregator or feed reader capable of reading feed formats such as RSS or Atom .
Certain podcasts can even be live and interactive. Dozens of podcast enthusiasts can be on at once, with the "host" being able to control their audience in the same way a radio host can.
Podcasting in Education
A new way to inspire learning
Podcasting offers an ideal tool for the creative expression of knowledge preferred by today's students, and provides an exciting way for students and educators to explore and discover educational content.
Podcasts are audio or video files that are automatically delivered over a network, then played back on any Mac, PC, or iPod.
When students create a podcast for class, they not only learn the content in a creative way, they learn 21st-century communications skills at the same time.
Create. Communicate. Share.
Podcasting allows educators to take their students beyond traditional assignments by allowing them to include voice recordings, photos, movies, and sound effects to share their knowledge.
For example, students can draft and perform scripts as a writing assignment, create a visual progress report for an ongoing project, or submit a recorded version of a science presentation.
Podcasting is also a great way for educators to deliver content to their students.
They can distribute homework assignments, record book narration for beginning readers to read along with, or create foreign language lessons that students can review at their own pace. – through Audacity.
Learning how to:
find useful podcasts
Subscribe to podcasts
Put podcasts on your IPod
ITunes Store (accessed through iTunes or web).
From iTunes store ( from iTunes help)
Podcasts are downloadable radio-style shows. Some podcasts also show video.
You can download free podcasts from the iTunes Store. Some websites charge for podcasts.
To download a podcast from the iTunes Store:
Click iTunes Store
Click Podcasts, and then click a podcast to see a list of recent episodes.
When you find a podcast you want to download, do one of the following:
To download a single episode, click Get Episode.
To subscribe to a podcast, click Subscribe. iTunes downloads the most recent episode. As new episodes become available, they are automatically downloaded to iTunes (when you are connected to the Internet).
Choose Edit > Preferences and then click Podcasts to do the following:
Change the number of episodes iTunes downloads.
Change how often new podcasts you subscribe to are downloaded.
Set iTunes to delete podcasts after you've listened to them.
To unsubscribe to a podcast, select a podcast or episode and then click Unsubscribe (at the bottom of the iTunes window).
If you know the Internet address of a podcast, you can subscribe to it without using the iTunes Store. Choose Advanced > "Subscribe to Podcast" and then enter the URL. You can usually find the URL of a podcast on that podcast's webpage.