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unit 5/02_Web_Mining.md

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+# Web Mining
+
+**Web Mining** is using data mining techniques to discover useful information from the World Wide Web.
+
+## Types of Web Mining
+
+### 1. Web Content Mining
+- **What**: Mining the **actual content** of web pages.
+- **Data**: Text, images, audio, video.
+- **Example**: Analyzing reviews on Amazon to see if people like a product (Sentiment Analysis).
+
+### 2. Web Structure Mining
+- **What**: Mining the **links** (hyperlinks) between pages.
+- **Goal**: To find important pages (Authorities) and pages that link to many others (Hubs).
+- **Example**: Google's **PageRank** algorithm uses this to rank search results.
+
+### 3. Web Usage Mining
+- **What**: Mining **user activity** logs.
+- **Data**: Server logs, browser history, clicks.
+- **Example**: Analyzing which pages users visit most often and where they leave the site.