Key difference: Wiki is a collaborative website, which can be edited, updated and deleted by its relevant users, while a Blog is a personal website usually created by an individual to share information.

Ward Cunningham is the developer of the first wiki software WikiWikiWeb, originally described it as "the simplest online database that could possibly work".  "Wiki" (pronounced ['witi'] or ['viti']) is a Hawaiian word which means "fast" or "quick".

Wiki is a web application, which is edited, updated, deleted and modified in collaboration with the other founders of the website. The text used for the edition is any markup language or a rich-text-editor. There are many sites running on different types of wiki software.

Wiki is a type of content management system that differs from a blog or most other such systems. Wikis have little implicit structure, which emerges according to the needs of the users. It can serve many different purposes, which includes both public and private, including knowledge management, note-taking, community websites and intranets. There are editing rights which may permit the changing, adding or removing of the material. There are also other permits used for accessing the sites along with the other rules imposed to organize the content.

Wiki has some specific characteristics on which it works, such as, it invites all users to edit any page or to create new pages within the wiki website. The wiki often uses only a plain-vanilla web browser without any extra add-ons. It promotes meaningful topic associations between different pages by making the page link creation easy and showing whether an intended target page exists or not. It is not a carefully crafted site for casual visitors. Instead, it seeks to involve the visitor in an ongoing process of creation and collaboration which constantly changes the web site landscape.

The short form, "blog" comes from “web log”, coined by Peter Merholz, who jokingly broke the word weblog into the phrase we blog in the sidebar of their blog Peterme.com in April or May 1999, from then the name Blog got famous.

A blog is a discussion or informational site published on the World Wide Web that consists of discrete entries ("posts") typically displayed in reverse chronological order (the most recent post appears first).

Blogs were previously the work of a single individual, which consisted of occasional small groups, and often covered a single subject, but now they are "multi-author blogs" (MABs), which are posts developed, written and professionally edited by a large number of authors. These MABs create the blog traffic for the newspapers, other media outlets, universities, think tanks, interest groups and institution accounts. Blogs along with the web-publishing-tools facilitated to the non-technical users for the posting of contents. They are edited and published with the knowledgeable technologies, such as the HTML and FTP.

Blogs are interactive sites, which provide the conversation between the web users and content managers. They are responsible for providing the general information regarding any content. Generally, they are formed to advertise and publish any services or knowledgeable products and are mostly used for private and personal purposes. A typical blog combines the text, images, and links to other blogs, web pages, and other media related to the topic. The ability of readers to leave comments in an interactive format  plays an important contribution to the popularity of many blogs.

Comparison between Wiki and Blog:

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