# Overview

Before learning how to use each tool, it’s worth knowing where we get our data from.

At Ahrefs, we crawl the web much like search engines do: using crawlers.

Our crawler is called AhrefsBot. It’s the #1 most active SEO crawler (and [8th most active crawler](https://radar.cloudflare.com/traffic/verified-bots) after Google’s and Bing's), visiting over 8 billion web pages every 24 hours and updating its index every 15–30 minutes.

Here’s how it works:

1. Our crawler starts from a big list of known URLs.
2. These URLs are then sent to the Scheduler, which decides when a URL should be crawled.
3. When a URL is ready to be analyzed, AhrefsBot will send the URL to the Crawler and download its contents; all while strictly respecting the allow/disallow rules set in the robots.txt file.
4. The crawler will deliver the raw data to the Parser, which extracts links on that page, the title, and other relevant metadata.
5. The extracted data is then sent to the Indexer.
6. It’s then added to the Link Index and made available in various reports in Ahrefs.

This is a linear and simplified explanation of how our crawler works. In order to continuously discover new pages and increase the size of our backlink index, we feed our list of URLs by surfacing new links from:

- Parsed data
- Redirects found via the Crawler

Currently, we show live link data and links that were deleted in the last 60 days.

## Module 1. Ahrefs’ Crawler and Index
- **Duration**: 15 min
  - **Overview**: 4:38
  - **Crawl budget**: 5:15
  - **Crawler FAQs**: 5:21

## Module 2. Ahrefs SEO metrics
- **Duration**: 22 min

## Module 3. Exploring your Ahrefs account
- **Duration**: 10 min

## Module 4. Dashboard
- **Duration**: 2 min

## Module 5. Site Explorer
- **Duration**: 44 min

## Module 6. Keywords Explorer
- **Duration**: 30 min

## Module 7. Site Audit
- **Duration**: 30 min

## Module 8. Rank Tracker
- **Duration**: 12 min

## Module 9. Content Explorer
- **Duration**: 12 min

## Module 10. Competitive Analysis
- **Duration**: 5 min

## Module 11. Alerts
- **Duration**: 7 min

## Module 12. Toolbar
- **Duration**: 4 min

### About this course [How to Use Ahrefs](/content/academy/how-to-use-ahrefs/index.html)
- **Total Lessons**: 62 
- **Total Duration**: 3h 18m

**What you’ll learn**
- How to analyze yours and your competitors’ websites with Site Explorer
- How to increase your AI visibility in LLMs with Brand Radar
- How to master keyword research with Keywords Explorer
- How to improve your on-page and technical SEO with Site Audit
- How to track and improve your Google rankings with Rank Tracker
- How to find untapped keyword and link building opportunities with Content Explorer

### Course by

**Andrei Țiț** is a product marketer at Ahrefs. He develops content to help you make the most out of Ahrefs.

**Sam Oh** is VP of Marketing at Ahrefs. He incorporates his commitment to education and love for entrepreneurship into actionable and easy-to-digest tutorials.

### Certification Exam
- **Questions**: 67 questions

Take the course exam to test what you’ve learned. Pass it and you’ll get a personal certificate signed by our educators and Ahrefs.

[Take exam](/content/academy/how-to-use-ahrefs/exam/index.html) 
An Ahrefs account is required to take this exam. Sign up for an [Ahrefs Free account](/content/free/index.html) or [paid subscription](/content/pricing/index.html) if you don’t have one.