Recall & Review
beginner
What is the main purpose of a web crawler?
A web crawler automatically browses the internet to collect and index web pages for search engines or data analysis.
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beginner
What is a URL frontier in a web crawler?
The URL frontier is a queue or list that stores URLs to be visited next by the crawler.
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intermediate
Why is politeness important in web crawling?
Politeness means respecting website rules like robots.txt and limiting request rates to avoid overloading servers.
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intermediate
What role does the parser play in a web crawler?
The parser extracts useful information and new URLs from the downloaded web pages for further crawling.
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intermediate
How can a web crawler avoid visiting the same page multiple times?
By maintaining a visited URL set or database to track and skip URLs that have already been crawled.
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What component stores URLs waiting to be crawled?
✗ Incorrect
The URL frontier holds URLs that the crawler will visit next.
Which file tells a crawler which pages it should not visit?
✗ Incorrect
robots.txt instructs crawlers about allowed and disallowed pages.
What is the main reason to limit the crawl rate?
✗ Incorrect
Limiting crawl rate prevents harming website performance.
Which component extracts links from a web page?
✗ Incorrect
The parser reads the page content and finds new URLs.
How does a crawler avoid visiting duplicate pages?
✗ Incorrect
Tracking visited URLs helps skip duplicates.
Explain the main components of a web crawler and their roles.
Think about how URLs are stored, fetched, processed, and tracked.
You got /5 concepts.
Describe how a web crawler respects website rules and avoids overloading servers.
Consider both technical and ethical aspects.
You got /4 concepts.