Astroturfing: fake grassroots campaign that seeks to create the impression of legitimate  buzz or interest in a product, service or idea. Often this movement is motivated by a payment or gift to the writer of a post or comment or may be written under a pseudonym.

Blog: online journal that's updated on a regular basis with entries that appear in reverse chronological order.

Crowdsourcing: harnessing the skills and enthusiasm of those outside an organization who are prepared to volunteer their time contributing content or skills or solving problems.

Feed: format that provides users with frequently updated content. Content distributors syndicate a Web feed, enabling users to subscribe to a site's latest content. By using a news reader to subscribe to a feed, you can read the latest posts or watch the newest video on your computer or portable device on your own schedule.

Hastag: community-driven conversation for additional context and metadata to your tweets. Similar to tags on Flickr, you add them in-line to your Twitter posts by prefixing a word with a hash symbol (or number sign). Twitter users often use a hashtag like #socialmagnetmar to aggregate, organize and discover relevant posts.

Microblogging: act of broadcasting short messages to other subscribers of a web service. On Twitter, entries are limited to 140 characters, and applications like Plurk and Jaiku take a similar approach with sharing bite-size media. Probably a better term for this may be 'microsharing.'

Podcast: digital file (usually audio but sometimes video) made available for download to a portable device or personal computer for later playback. A podcast also refers to the show that comprises several episodes. A podcast uses a feed that lets you subscribe to it so that when a new audio clip is published online, it arrives on your digital doorstep right away.

RSS (Really Simple Syndication): Web standard for the delivery of content-blog entries, news stories, headlines, images, video-enabling readers to stay current with favorite publications or producers without having to browse from site to site, blogs and news content using a news reader. All blogs, podcasts and videoblogs contain an RSS feed, which lets users subscribe to content automatically and read or listen to the material on a computer or a portable device. Most people use an RSS reader, or news aggregator, to monitor updates.

Search Engine Marketing (SEM): a series of online tactics that, when combined with SEO, helps to attract customers, generate brand awareness and build trust. SEM (sometimes called search marketing) seeks to increase websites' visibility chiefly through the purchase of pay-per-click ads and paid inclusion.

Search Engine Optimization (SEO): is the process of arranging your website to give it the best chance of appearing near the top of search engine rankings. As an Internet marketing strategy, SEO considers how search engines work and what people search for. Optimizing a website primarily involves editing its content, identifying high-traffic keywords and improving the site's layout and design.

Social Bookmarking: method by which users locate, store, organize, share and manage bookmarks of Web pages without being tied to a particular machine. Users store lists of personally interesting Internet resources and usually make these lists publicly accessible. Delicious is the best known social bookmark site.

Social Media: works of user-created video, audio, text or multimedia that are published and shared in a social environment, such as a blog, podcast, forum, wikl or video hosting site. More broadly, social media refers to any online technology that lets people publish, converse and share content online.

Social Media Optimization (SMO): set of practices for generating publicity through social media, online communities and social networks. The focus is on driving traffic from sources other than search engines, though improved search ranking is also a benefit of successful SMO.

Social Networking: the act of socializing in an online community. A typical social network such as Facebook, LinkedIn, MySpace or Bebo allows you to create a profile, add friends, communicate with other members and add your own media.

Tags: keywords added to a blog post, photo or video to help users find related topics or media, either through browsing on the site or as a term to make your entry more relevant to search engines.

Troll: someone who posts controversial, inflammatory, irrelevant or off-topic messages in an online community, such as an online discussion forum or chat room, with the primary intent of provoking other users into an emotional response or to generally disrupt normal on-topic discussion.

Tweet: a post on Twitter a real-time social messaging system. While all agree on usage of tweet as a noun, people disagree on whether you 'tweet' or 'twitter' as a verb. RT stands for retweet: Users add RT in a tweet if they are reposting something from another person's tweet.

Twitterverse: Akin to blogs and the blogosphere, the Twitterverse is simply the universe of people who use Twitter and the conversations taking place within that sphere.

UGC (User Generated Content):  industry term that refers to all forms of user-generated materials such as blog posts, reviews, podcasts, videos, comments and more.

Web 2.0: refers to the second generation of the web, which enables people with no specialized technical knowledge to create their own websites to self-publish, create and upload audio and video files, share photos and information and complete a variety of other tasks. In this new world, the Internet becomes a platform for self-expression, education and advocacy that 'regular people' can use on their own without having to go to an expert to do it for them in contrast to the less interactive publishing sites of Web 1.0.

Web Analytics: measurement, collection, analysis and reporting of Internet data for the purpose of understanding who your visitors are and optimizing your website.

Widget: (sometimes called a gadget, badge or applet) small block of content, typically displayed in a small box, with a specific purpose, such as providing weather forecasts or news, that is constantly updating itself (typically vis RSS). Widgets make it easy to add dynamic content to your site or blog.

Wiki: collaborative website that can be directly edited by anyone with access to it. Small teams often find that they can accomplish a task easier by creating a collaborative online workspace using wiki software such as pbworks, Social text or media wiki.

Word-of-Mouth Marketing: (sometimes called grassroots marketing or conversational marketing) umbrella term for dozens of techniques that can be used to engage and energize customers. By building relationships with influencers through WOM, marketers can get people to become so enthusiastic about a cause, product or service that they drive sales through conversations.

WordPress: popular open source blog publishing application.