This article is about the type of website. For the record of web server activity, see server log.
A weblog, or simply a blog, is a website which contains periodic, reverse chronologically ordered posts on a common webpage. Such a web site would typically be accessible to any Internet user. Part of the reason "blog" was coined and commonly accepted into use is the fact that in saying "blog", confusion with server log is avoided. Individual posts (which taken together are the blog or weblog) either share a particular theme, or a single or small group of authors.
The totality of weblogs or blog-related webs is usually called the blogosphere. The format of weblogs varies, from simple bullet lists of hyperlinks, to article summaries with user-provided comments and ratings. Individual weblog entries are almost always date and time-stamped, with the newest post at the top of the page. Because links are so important to weblogs, most blogs have a way of archiving older entries and generating a static address for individual entries; this static link is referred to as a permalink. The latest headlines, with hyperlinks and summaries, are offered in weblogs in the RSSXML-format, to be read with a RSS feedreader.
Before blogging became popular, digital communities took many forms, including Usenet, email lists and bulletin boards. In the 1990's electronic form software, such as WebX, created running conversations with threads. Many of the terms from weblogging were created in these earlier media. For example troll, a person who disrupts a discussion, dates back to Usenet. The word "thread" from email lists and usenet as well. The verb "to post" from electronic bulletin boards.
Blogging combined the personal web page, with tools to make linking to other pages easier, specifically blogrolls and trackbacks, as well as comments. This way, instead of a few people in control of threads on a forum, or anyone able to start threads on a list, there was a moderating effect that was the personality of the weblogs owner.
"Weblogs are often-updated sites that point to articles elsewhere on the web, often with comments, and to on-site articles. A weblog is kind of a continual tour, with a human guide [whom] you get to know. There are many guides to choose from, each develops an audience, and there's also comraderie and politics between the people who run weblogs, they point to each other, in all kinds of structures, graphs, loops, etc." -- Dave Winer, 
The shorter version, "blog," was coined by Peter Merholz who in April or May of 1999 broke the word weblog into the phrase "wee' blog" in the sidebar of his weblog . This was interpreted as a short form of the noun  and also as a verb, to blog, meaning "to edit one's weblog or a post to one's weblog". Usage spread during 1999 and the word was popularized by Pyra's creation of their weblog service Blogger. As of March 2003, the Oxford English Dictionary included the terms weblog, weblogging and weblogger in their dictionary. 
One of the pioneers of the tools that make blogging more than merely websites that scroll is Dave Winer of the Berkman Center at Harvard University. One of his most important contributions was the creation of servers which weblogs would "ping" to show that they had updated. This made it possible for blogs to easy "trackback" other blogs that referenced a particular story, a key feature of blogging.
In early 2002, blogs began to spring up to support the invasion of Iraq, these "war bloggers" were primarily from the right end of the spectrum, and included Instapundit and Little Green Footballs. The first "blog" driven controversy is probably associated with the fall of Trent Lott, where bloggers found quotes from his previous speeches which were taken to be racist, and "kept the story alive" in the press.
By this point blogging is enough of a phenomenon that howto manuals had begun to appear, primarily focusing on using the tools, or creating content. But the importance of a blog as a way of building an electronic community had also been written on, as had the potential for blogs as a means of publicizing other projects.
Through 2003, weblogs gained increasing notice and coverage for their role in breaking, shaping or spinning news stories. The triggering event was the sudden emergence of an opposition to the Iraq war which was not rooted in the traditional anti-war left. The blogs which gathered news on Iraq, both left and right, exploded in popularity, and Forbes magazine covered the phenomenon. The use of blogs by political candidates, particularly Howard Dean and Wesley Clark cemented their role as a news source, while the increasing number of experts who blogged, including Daniel Drezner and J. Bradford DeLong gave the blog world a cachet among regular journalists.
The Iraq War was the first "blog war" in another way - bloggers in Baghdad gained wider readership, and one published a book of his blog. Reading the thoughts of people who were "on the spot" provided a counterpoint, if not a counterweight, to official news sources. Blogs were often used to draw attention to obscure news sources, for example posting links to the traffic cameras in Madrid as a huge anti-terrorism demonstration filled the streets in the wake of the M11 attack. Bloggers would often provide nearly instant commentary on televised events, which became a secondary meaning of the word "blogging", such as "I am blogging Rice's testimony", i.e. "I am writing my reactions to Rice's testimony as I watch it."
In 2004, the role of blogs became increasingly mainstream, as political consultants, news services and candidates began using theme as tools for outreach and opinion formation. Minnesota Public Radio broad cast a program by Christopher Lydon and Matt Stoller called "The Blogging of the President", which covered the transformation in politics that blogging seemed to presage. The Columbia Journalism Review began regular coverage of blogs and blogging. Anthologies of blog pieces began to reach print, and blogging personalities began appearing on radio and television.
Many more advanced bloggers prefer to generate their blogs by using server-side software tools such as Movable Type, WordPress, and Manila to publish on their own Web site or a third party site, or to host a group of blogs for a company or school. Such programs provide greater flexibility and power, but require more knowledge. If they provide a Web interface for editing, server-based systems may reduce the ease of creating and editing text for travellers, some of whom like to produce their travelblogs from Internet cafes as they travel around the globe.
Many blogging tools have also been developed to improve the blogging experience, with commonly used ones providing blogrolls and feedback comment systems. Well known examples of these are blogrolling and the commenting system HaloScan. Tools such as Ecto and w.bloggar allow users to maintain their Web hosted blog without the need to be online while composing or editing posts. Enhancements to weblog technology continue to be developed, such as the TrackBack feature introduced by Movable Type in 2002 and subsequently adopted by other software companies (e.g., Userland) to enable automatic notification between websites of related content -- such as a post on a particular topic or one which responds to a post on another blog .
Blogs with features such as TrackBack are credited with complicating search engine page ranking techniques  and confusing (perhaps deliberately gaming) search engines that try to establish context.
Web hosting companies and online publications also provide blog creation tools, such as Salon, Tripod, and America Online, which calls its subscriber blogs "journals."
Often, the word blog is used to describe an online diary or journal, such as LiveJournal. The weblog format of an online diary makes it possible for users without much experience to create, format, and post entries with ease. People write their day-to-day experiences, complaints, poems, prose, illicit thoughts and more, often allowing others to contribute, fulfilling to a certain extent Tim Berners-Lee's original view of the World Wide Web as a collaborative medium. In 2001, mainstream awareness of online diaries began to increase dramatically.
Online diaries are integrated into the daily lives of many teenagers and college students, with communications between friends playing out over their blogs. Even fights may be posted in the diaries, with not-so-veiled insults of each other easily readable by all their friends, enemies, and complete strangers. Online diaries may also be a bane to job seekers, if their diaries are discovered by potential employers.
Political blogs attracted attention because of their use by two insurgent political candidates in 2003: Howard Dean and Wesley Clark. Both gained political buzz on the internet, and particularly among bloggers, before they were taken seriously by the establishment media as candidates. Joe Trippi, Dean's campaign manager, made the internet a particular focus of the campaign. Both candidates stumbled in the end, but were, at one time or another, thought of as front runners for the Democratic Nomination.
BlogPulse - Full-text search engine for blog postings. Also analyzes Top Links, Key People, Key Phrases, and produces BlogBites every day. Showcases trend graphs from the blogosphere. Allows you to create your own trend graphs.
Blogshares - A fantasy stock market where weblogs are the companies. Players invest fictional dollars on shares in blogs. Blogs are valued by their incoming links and add value to other blogs by linking to them. Prices can go up or down based on trading and the underlying value of the blog.
Weblogs.com - a list of weblogs updated in the last three hours
Human World news, reports, opinions, reviews and ideas on sustainability, natural food, food safety, food supply, and our personal and tribal health and future in our urban environment. http://human.editthispage.com/
The American Mind A daily weblog of politics and culture. http://www.angelfire.com/wi/shackbar/
Blog News - Topix.net News on blogs and blogging collected from diverse sources on the web. http://www.topix.net/news/blogs
Anythink.org Newscast Yet another daily roundup of interesting sites, sounds and stuff from around the web. http://www.anythink.org
The Mahablog News, opinion, and discussion critical of the Bush Administration. http://www.mahablog.com/
Insults Unpunished Current political event commentary from Robert K. Prather. http://www.insultsunpunished.com/
WxBLOG A Web log about weather. http://cumulus.blogspot.com/
Judicious Asininity Roundup of select news, views, commentary, and editorials from world wide sources with comments from the editor. http://www.asininity.com/
Pearse Frazier's Letters from the Ledge Updated often with opinion, news, and reviews on art, philosophy, and economics, including music, books, tv, movies, religion, politics, technology, taxes, and love. http://pearse.thefraziers.org/
Schwartzreport Schwartzreport is a daily publication in favour of the earth, the inter-connectedness and interdependence of all life, democracy, liberty, and things that are life affirming. It also warns readers about actions, and events that threaten those values. Stories have been vetted for accuracy by either a significant peer reviewed research journal or, at the least, a major journalistic publication. http://www.schwartzreport.net
Metafilter Community based news oriented weblog. http://www.metafilter.com/
Insurrection.org Everything of what's wrong with the world, and very little of what's right. Mind candy for the masses. http://insurrection.org/
Skyhen.org Weblog of alternative media sources and different perspectives on current events, social issues and politics. http://www.skyhen.org/
Kevin Sites Blog Weblog by CNN correspondent Kevin Sites, with current reports and pictures, including coverage of Iraq. http://www.kevinsites.net/
UXblog User experience in the context of emerging technology and advanced business strategy. http://www.challishodge.com/
Rhetorica Regularly updated commentary and analysis of rhetoric and spin in politics and journalism. http://rhetorica.net
Wordforge a Weblog Sparks fly when a boomer blacksmith turned paper-shuffling environmental bureaucrat tries to make sense of our world. Wit, sarcasm and satire abound. http://www.wordforge.freeservers.com/blog.htm
Newsfilter News for the "Shmoes", by the "Shmoes." No elitists allowed. http://www.newsfilter.org
Speckz.com Speckz.com is your portal to everything computer related! http://www.speckz.com
On The Third Hand A blog linking to world news and view, and commenting on same. http://site-essential.com/index.shtml
From the Desk of Dane Carlson Dane Carlson's weblog of libertarian politics, Mars, Europa, latin american literature, social discourse and the web. http://www.carlsoncarlson.com/dane/
newsqueak.com News and views on what makes life interesting: technology, science, sports, entertainment, lifestyle, sex, and humor. Includes email subscriptions, discussion forums, polls, and chats. http://www.newsqueak.com
Amygdala Gary Farber's twisted take on news, politics, the media, history, science, science fiction, and science fiction fandom. http://www.amygdalagf.blogspot.com
Electric Venom Constantly updated news, current events, analysis and punditry from a decidedly conservative, sarcastic and educated perspective. http://www.electricvenom.com
iRights Keeping watch on the collision of conventional rights (such as free speech) and the internet, and researching new expressions of those rights. http://www.jerf.org/irights/
Warblogs:cc Content from war blogs from around the world. http://www.warblogs.cc/
Blue Chair Blog Liberal commentary on current events, arts and writing. http://bluechair.port5.com/
Pacific Views Liberal blog commentary on the environment, politics, technology, culture, and periodically, space colonization. http://www.pacificviews.org/
Guardian Unlimited weblog Links to noteworthy journalism from around the web, from the UK online news service of the year. http://www.guardian.co.uk/weblog
Trivium News, commentary and fun things found on the Internet. http://www.trivium.blogspot.com/
Don't Be A Shamed A news weblog, with a bit of politics and culture thrown in, written by a DC-based libertarian-conservative Republican. http://shamed.blogspot.com
The Geekery Biased and unbalanced news. http://www.gotthegeek.com
CulturePimp Proving that not all of us below the Mason-Dixon line are beer-swilling, Baptist fundamentalist, NRA-certified, NAACP-hating hillbillies; there are also a lot of pot-smoking, agnostic/atheist, ACLU-certified, Heritage Foundation-hating hillbillies too. http://www.culturepimp.com
MoronWatch The latest in moronic thought and comment from around the globe. http://moronwatch.blogspot.com
Newsfinder Dedicated to discoveries, trends in the humanities, sciences, travel news, x-treme sports, martial arts, alternative, meditation, technology news, culture, sport news, special news. http://www.newsfinder.org/
Spinline.net Opinion on politics and technology. Also the Opinion Roundup, a handy summary of the opinions of editorial pages, pundits, and politicians. http://spinline.net
Surveillance Random comments on events of the day. http://www.surveillance.blogspot.com
The Stationmaster Magnus Bernhardsen is a anti-war, anti-EU, leftwing Norwegian who writes mostly about politics. http://magnus.blogspot.com
hbo3.com Primary interest is politics and current events, also writes about hobbies and other interests. Tries to maintain good research standards and express honest opinions. http://www.hbo3.com/
NextDraft News A newsletter and website that covers all the news from politics to pop culture, from Jerusalem to JLo. It's your dinner party prep. http://www.nextdraft.com
Breakfast Tacos Community blog: politics, news, and interesting sites. http://www.breakfasttacos.com
The Off Thing The off the track follow up on science and culture. http://www.naganaga1.blogspot.com
Backstage with Supak Watching the Junta in the White House and other stories of note with stagehand Scott Supak, backstage in Hollywood. Features links, quotes, pictures, and free stuff. http://supak.blogspot.com
Global News Watch Daily (mostly) look at world news from a conservative, pro-US perspective. http://www.globalnewswatch.com/
Plastic News stories categorized into sub-sections that users can comment on. http://www.plastic.com/
Catch A portal for sharing weird, cool and/or interesting links. A place to discuss important news. A community of smart people who enjoy exchanging witty repartee with other smart people from around the world. http://www.catch.com
Just News Selected news from various sources. http://justnews.blogspot.com
Commentariat A discussion of current events and politics, with a leavening of features and interesting discoveries and essays. http://www.hathaby.net/
The PostNationalist Eclipse of the nation-state. From taxation and regulation to banking and commerce, traditional governments are being subsumed by a technological behemoth - an onslaught of accelerated, democratized, and stealth-like communications. http://thepostnationalist.com
GregBender dot Com News News that Greg Bender thinks relevant, mostly computer/hardware/software news. http://www.gregbender.com
POE News Daily odd ball and political news with an active forum to discuss current events. http://www.poe-news.com/
Quentin Stafford-Fraser's notepad A weblog mostly about IT, especially Linux, Open Source, and Apple, but which often runs off into other areas... http://www.statusq.org/
DC Dogs News DC Dogs : DC-MD-VA Dog News - Rescue, volunteer & play with dogs http://dc_dogs.blogspot.com
ChimpNews Chimpanzee news & views from around the world http://chimpnews.blogspot.com
People are stupid Personal writing, commentary and links. http://blogs.salon.com/0001018/
War Blogging Warblogging.com examines whether civil liberties and perpetual war can coexist. Includes news snippets and commentary and the Evil Index(tm), a measure of how many times people like John Ashcroft and Usama bin Laden are mentioned on weblogs. http://www.warblogging.com
The Comedian Blog with links to news stories of interest, plus commentary. http://comedian.blogspot.com
The Signature Monitor An online unofficial charter high school newspaper, run by the students. http://signaturemonitor.blogspot.com
The Online Journalism Report Literate, witty and wise tracking of developments in the wide world of online journalism. Every Tuesday and Friday. http://www.ojr.org/ojr/spike/index.php
Unknown News News of interest to the interested: The good news along with the bad, and especially the ugly. http://www.unknownnews.net/
Secular Blasphemy A look at science and current affairs with a freethought twist. http://blogs.salon.com/0001561/
Ready Fire Aim Interesting news and stats in media, business, technology, and life in San Francisco. http://www.bloggingnetwork.com/Blogs/Blog.aspx/readyfireaim/
Nova Lounge: the Blog A different version of the same take.. only better. http://www.trancewave.com/novalounge/blog
Cupie Spew for the Masses Book reviews, general rants and a daily quest to find the answers in life. http://cupiespew.blogspot.com/
Nathan Newman News analysis with an emphasis on labor and progressive politics. http://www.nathannewman.org/log/
The Soapbox News and commentary site that includes both the left and right views of a monthly topic, message board, a conspiracy corner, and reader submissions. http://www.valleysoapbox.com
Seriously Though News blog welcoming comments and discussion. http://www.seriouslythough.com
CanadianGeek The ramblings of a 20-something Canadian. Pop culture, technology, current affairs and personal stories. http://digiverse.net/canadiangeek
Location Location Location Real estate blog reviewing news, academic, and commericial realty and investing sites. http://real-estate-properties.com/
Michael Wong Weblog offering Internet marketing news, press releases, product announcements, statistics, tips and commentary. http://www.michaelwong.com/
Net Lease News News on sale leaseback transactions, lease financings, and the sale of single tenant net leased real estate investments worldwide. Weblog editor: Patrick R. Mickey. http://netleasenews.blogspot.com/
David Lawrence Blog referring to news stories and flash files of note. http://heywait.blogspot.com/
PublicApproval.com Online polling blog asking you what you think of current topics and trends. http://www.publicapproval.com
Twin Cities Babelogue Front page blog/ index to City Pages' online weblog community, which is comprised of staff-written and guest blogs. http://babelogue.citypages.com:8080/
NewsHeadLinks An eclectic collection of interesting news links. http://www.newsheadlinks.com/
The Carpetbagger Report Commentary, analysis, and tirades on politics in America. http://www.thecarpetbaggerreport.com
SmashTech Wardriving, political opinions, geek news, it's all here. http://www.smashtech.net
BlogAmY.com A weblog of social commentary, news stories, politics, and occasional creative ranting. http://www.blogamy.com/
The RipZAW A Libertarian-Democratic leaning Californian-turned-Pennsylvanian college student's weblog. Covering politics, sports, religion, politics, entertainment, and politics. 100% organic, PABA-free. http://ripzaw.blogspot.com
Solid Empire Vent your political and social frustrations. A place for weird, crazy, and funny stuff. http://www.solidempire.com
Military News Watch A reality check for news coverage of military issues. http://militarynewswatch.blogspot.com/
BTC News An acerbic, satirical, outraged and occasionally outrageous look at news, politics and miscellaneous oddities. http://www.btcnews.com
The Practical Hippie News tidbits, interesting thoughts of the day, and other things TBD. http://www.practicalhippie.com/weblog
The Fulcrum The blog of a liberal, humanist, ex-military pilot. http://thefulcrum.blogspot.com
Bloggers.ca Bloggers.ca is a news blog, with a touch of humour. http://www.bloggers.ca/
Patriot Paradox This is a weblog with opinions and commentary on news, religion and personal life. http://www.patriot-paradox.com
WebWarrior NGC News, forums, videos, images. http://www.webwarrior.net
Fables of the Reconstruction Blog about law, politics, sex and Philadelphia, written by an anonymous kinky liberal lawyer. http://mithras.blogs.com
PR Bop Weird and wonderful selections from press release wires. http://www.prbop.com
UFO News Blog UFOs, extraterrestrials sightings and news. Other paranormal and unexplained news too. http://www.cosmicparadigm.com/ufonews/
ContraWeb Blog on activism, environmental issues, and news about under-reported current affairs and politics. http://contraweb.weblogs.us/
Tales Of Ordinary Madness An alternative, incisive look at what's in the news with special attention paid to UK topics. http://horselatitudes.blogs.com/
Everything I Know Is Wrong Political and philosophical comentary from a classical liberal (in the U.S. that means conservative) viewpoint. http://www.everythingiknowiswrong.com
ThePolitic Canadian conservative weblog that publishes daily commentary on political events in Canada. http://www.thepolitic.com
TheTravisty Funny and cool video clips. Televisions skits, cartoons, jokes and humor. Flash games and cartoons, tons to do. http://thetravisty.com
Voluntary Exchange Posts on current events and culture, focused from an economic perspective. http://voluntaryxchange.typepad.com
Blimey! Have your say on the latest UK news from entertainment to current affairs or just chat with other Brits on the message board. http://www.blimey.com
Hersh, Mike Political commentary from a writer, lawyer, and activist. http://www.mikehersh.com/
Fark.com Interesting, bizarre and amusing news stories, along with regular photo manipulation contests. http://www.fark.com/
Back to Iraq 2.0 A weblog that focuses on Iraq, Kurds, and the Middle East. Maintained by journalist Christopher Allbritton. http://back-to-iraq.com/
net.Headlines A once-a-day glance at headlines you are not likely to find on most news sites. http://e-portals.org/links
Big Blog Brings you the latest in breaking news. http://bigblog.com/
Figby.com Bits about technology, books, publishing, and miscellany from the author of several computer books. A display of customizable headlines from hundreds of sites. And mice. http://www.figby.com/
ElianWatch documenting the Elian Gonzalez story. http://www.angelfire.com/wi/shackbar/elianwatch.html
Adland Ad-rag.com Ad news by the adgrunts, community ad blog, commercial archive collection. http://ad-rag.com
Blog.org Daily updates on the Internet and its social and public policy implications useful websites, political/ cultural musings. From David Brake a UK-based academic (PhD researcher @ the LSE), Internet consultant and journalist. http://blog.org/
What Does Not Change My writing on politics, Rilke, some photography and other little web projects. http://www.whatdoesnotchange.org/
Centrax Blog Server E-learning news, blogs, and expert opinions developed and hosted by Centrax Corporation. http://www.centraxblog.com
This is News Weblog with general and internet news. http://thisisnews.pitas.com/
snowdeal.org | conflux A weblog that provides daily updates and links to news items and stories related to science and technology, culture, privacy and the media. http://snowdeal.org/
Danchan Daily news from around the net, high gear cool equipment reviews, tips on backpacking in central Europe, cgi/perl/mysql tutorials and a free weblogging service with no ads. http://www.danchan.com
SurfJones The sports and sports culture weblog, updated daily. http://newcitycgi.com/cgi-bin/php/surfjones/surfjones.php3
Stickybuffalo The finest in absolutely nothing since not long ago, particularly when it comes to liberal political whining and links to the bizarre and inane. http://www.stickybuffalo.com
Slackers Guild A user-driven online publication dedicated to those who enjoy being lazy and unproductive. http://www.slackersguild.com/
News Compass International news and current affairs. http://newscompass.blogspot.com/
The Urban Monk A human portal featuring "glo-cal" urban issues including news, critics and points of view unseen in mainstream or alternative press. Content is freely edited by a Montreal-based e-commerce consultant. http://urbanmonk.blogspot.com/
Crutons Tasty morsels floating in the ether. http://www.crutons.com
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