Okay, I need to create a professional and useful wiki document about "Wiki" under the categories of Technology -> Web Development -> Wiki Software. Let me start by understanding the requirements.

First, the structure: H1 title, overview section, multiple sections with H2 and H3, and references if needed. The content should be accurate, objective, detailed enough, easy to read, and use technical terms with explanations. Also, markdown formatting with proper headings, lists, tables, code blocks where necessary. The document needs to be at least 800 characters long.

Starting with the title: "위키" as H1. Then an overview section explaining what a wiki is, its purpose, key features, and maybe some history. Next sections could include types of wikis, how they work, popular examples, use cases, challenges, and references.

For the overview, I should define wiki, mention it's collaborative, allows editing, open-source vs proprietary. Maybe touch on the origin from Ward Cunningham's WikiWikiWeb in 1995.

In the sections, maybe break down into "정의 및 개념", "주요 특징", "작동 원리", "대표적인 위키 소프트웨어", "사용 사례", "도전 과제" (challenges). Each of these can have H2 headings. Under each H2, add H3 for sub-sections if needed.

For the main features, list things like collaborative editing, version control, hyperlinks, open access. Maybe explain each briefly with examples.

In the working principle section, talk about how users can edit pages via web interfaces, version history, permissions, and maybe mention some technical aspects like databases or APIs.

For popular software, include MediaWiki (used by Wikipedia), DokuWiki, Confluence, Tiki Wiki. Each could have a brief description, features, and use cases.

Use cases: businesses for internal documentation, educational institutions, open-source projects. Maybe give examples of each.

Challenges might involve security issues, vandalism, information accuracy, maintenance costs. Discuss these with possible solutions or mitigation strategies.

Need to ensure technical terms are explained. For example, when mentioning version control, explain it's tracking changes over time. When talking about APIs, mention they allow integration with other tools.

Check for markdown formatting: use # for H1, ## for H2, ### for H3. Use bullet points or numbered lists where appropriate. Maybe a table comparing different wiki software if needed.

Also, include references to sources like Wikipedia's history, official websites of the mentioned wikis, and any relevant studies or articles.

Make sure the language is clear and concise, avoiding jargon without explanation. Keep paragraphs short for readability. Ensure the total length meets 800 characters; since this is a detailed document, it should be sufficient.

Now, start drafting each section step by step, ensuring all requirements are met.