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Web Scrapers A Comprehensive Introduction

Learn all about web scrapers, and how it works. Explore the security aspects, common problems faced during web scraping, and practical solutions.



Sep 23, 2023

Web Scrapers: Everything You Need To Know About

Web scraping has become an essential tool for businesses and individuals alike. It allows you to extract valuable data and information from websites automatically. It saves you time and effort in manual data gathering.

Today, we will explore everything about web scraping. We will talk about web scrapers, how they work, and common problems encountered during the process. So, let's dive right in.

What Is Web Scraping?

Web scraping is also known as web data scraping or web data extraction. It refers to the automated collection of both structured and unstructured data from the internet. There are many uses for web scraping, including pricing monitoring, news monitoring, lead generation, price intelligence, and market research.

People and companies looking to gather freely accessible online data to gain valuable insights and make informed decisions often rely on web scraping. Suppose you have ever manually extracted data from a website by copying and pasting. In that case, you have already performed a similar task to a web scraper.

However, web scraping goes beyond manual extraction. This is because it uses machine learning and intelligent automation to retrieve billions of data points from the vast expanse of the internet. Ultimately, this eliminates the need for time-consuming manual processes.

Whether you are planning to use a web scraper or considering outsourcing the task to a web data extraction partner, it is vital to understand how web scraping works.

How Does Web Scraping Work?

Web scrapers function in a manner that is both simple and intricate. After all, websites are made for people, not for computers. Here is how web scraping works:

  • HTML Code Retrieval

    After that, the scraper loads the entire HTML code for the relevant page. Advanced scrapers can render the complete webpage, including Javascript and CSS elements.

  • Data Capture

    The scraper will either extract all the data on the webpage or only specific data chosen by the user prior to initiating the project.

  • Data Selection

    The user must specify the exact data they wish to extract from the webpage. For example, you might only be interested in the pricing and model information from an Amazon product page rather than customer reviews.

  • Data Export Finally, the web scraper exports all the gathered data in a more user-friendly format. While advanced web scrapers allow for alternative formats like JSON that can be utilized for an API, most web scrapers export data to a CSV or Excel spreadsheet.

This process transforms vast amounts of web data into structured datasets ready for analysis or other uses.

Security Of Web Scraping

Web scraping must be conducted responsibly to avoid legal repercussions and respect the destination website’s rules. Here are some best practices to ensure the security of web scraping:

1. Adhere To Robot Exclusion Standards (Robot.Txt)

This file provides explicit guidelines for proper conduct, including how often you can scrape, which URLs you can scrape, and which pages you should avoid. It’s typically located in the root directory of every website.

2. Slow Down The Crawler

While a bot can crawl a page quickly, speed often implies recklessness. Be respectful to the websites and slow down the bot by adding a 10–20-second delay between clicks.

3. Scrape At Off-Peak Times

Ideally, scrape the website during off-peak hours. This increases scraping speed and minimizes any potential impact on users.

4. Utilize A Headless Web Browser

A headless browser, which lacks a GUI, loads pages much faster than a conventional browser. It can also save time and resources by only loading the HTML component of the page rather than the entire website. Examples of headless browsers include Selenium, Puppeteer, and Playwright.

5. Watch Out For Honeypot Traps

A headless browser, which lacks a GUI, loads pages much faster than a conventional browser. It can also save time and resources by only loading the HTML component of the page rather than the entire website. Examples of headless browsers include Selenium, Puppeteer, and Playwright.

6. Adhere To Copyright Laws

Always consider copyright when preparing to scrape data. Many types of content, including articles, photos, databases, videos, etc., are often protected by copyright. Be aware that much of the information on the internet is copyrighted.

7. Adhere To GDPR

Respect local regulations and exercise utmost caution. Avoid scraping any personal information that could be used to identify an individual, such as names, addresses, phone numbers, emails, etc.

Problems Encountered When Web Scraping And How To Effectively Solve Them

Web scraping can encounter several challenges. Here are some of the common problems and their practical solutions:

Databases and Broken Links

Broken links and missing datasets can pose significant challenges for web scrapers. These issues can arise due to server downtime or changes in website architecture.

Solution: To solve this, use crawlers to scan websites for changes that could cause problems periodically. Ensure your scraper continuously scans the sites you’re scraping so you can adjust your approach as needed.

Basic HTTP Authentication

Users must authenticate themselves with a username and password when a website or web service uses basic HTTP authentication to restrict resource access. This can complicate scraping as the web scraper may need valid credentials to access the required information.

Solution: To address this, use specialized browser middleware to handle complex authentication requirements by automatically inserting site credentials.


Websites often use IP blocking to prevent bots or unauthorized traffic from accessing their content. If a website identifies an IP address it wants to block, it will add it to a blacklist, preventing any traffic from that IP.

Solution: Web scrapers often use changing IP addresses to prevent IP blocking. However, if a web scraper's IP address is on a blacklist, it won't be able to visit the website.

Connection Between Rotating Proxy And Web Scraping

otating proxies offer numerous advantages for web scraping. By constantly changing the IP addresses used to send queries, rotating proxies effectively circumvent IP banning and speed limitations that can hinder data extraction. Moreover, rotating proxies make it challenging for websites to block access based on IP address. Thus, it ensures uninterrupted scraping activities.

With rotating proxies, you can effortlessly bypass geo-restrictions, enabling you to connect from various nations. This proves invaluable when gathering data that is only accessible within specific regions or countries.


Web scraping is a powerful method for extracting necessary data from websites. You should understand how web scrapers work, address security concerns, and effectively solve common problems.

These can help you achieve the full potential of web scraping. And when combined with rotating proxies, web scraping becomes even more efficient. If you want a reliable proxy service provider, whether it is a rotating or cURL proxy, don’t hesitate to contact us today.

In terms of our proxy pool, we ensure that it is up-to-date with the latest resources and free from IP bans and 403 errors. In terms of speed, we have deployed nodes across three continents to enable users from different regions to access IPs faster, with speeds even reaching 100-200ms.

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