An Introduction to Web Scraping: What It Is and How It Works

Editorial Team

An Introduction to Web Scraping

You may have already heard of the term web scraping. However, do you know what it is and its essence? Worry not because we are about to answer this and many other relevant questions. This article covers what web scraping is, its uses, how it works, and a few tips that can help you gather information from multiple web sources. Let’s get started.

What is Web Scraping?

Web scraping is a web data collection technique used by data analysts and researchers to gather information from the internet, which is then stored in local files for easier manipulation and analysis. Most data researchers and analysts use web scraping proxies or bots programmed to crawl the internet and find relevant information faster, explaining why connecting to premium proxies is essential.

Types of Scrapable Data

Any type of data found on the internet including texts, reviews, videos, and images can be scrapped. However, be careful to avoid landing in trouble. A piece of good advice is to consider the data protection protocols of different jurisdictions and the relevant websites’ terms of service. 

Web Scraping Applications

Web scraping is an essential tool in data analytics. Here are some of its applications:


Web scraping is pivotal in marketing since information gathered from relevant websites can be used to build email and phone lists for lead generation. Common sources of email addresses and phone numbers are yellow pages and Google Maps business listings.

Data Research

Web scrapers are generally used to obtain structured data from several internet sources for academic and scientific research purposes.


Web scraping software and proxies are generally used to extract product data, including images, reviews, descriptions, and ratings, from e-commerce websites such as eBay and Amazon.

Data Analysis

Web scrapers allow you to obtain data from multiple sources and store them in a single spreadsheet or database for easy data analysis.


Companies use this data collection technique to obtain their competitors’ product prices and monitor competition.

Real Estate

Web scraping can be used to obtain details of houses listed on websites such as Zillow. Additionally, it can help you obtain the contact information of owners and agents.

Machine Learning

Web scraping is handy in machine learning projects as it can gather relevant data for testing and training machine learning models. It is instrumental when such data isn’t readily available.

Other uses of web scraping include sports betting odds analysis and determining hotel rooms and prices from relevant websites.

How Do Web Scrapers Work?

Web scrapers and proxies are used for scraping. Their working mechanisms differ from one to the next. However, they all follow three principles: requesting the server, extracting and breaking down the website’s code, and locally saving the data. Let’s expound on these principles.

Requesting the Server

Web scrapers make HTTP requests for information access to the relevant servers first. Note that these requests can be sent to one or multiple sites.

Extraction and Parsing

The next step after gaining access to a website is reading and extracting its code, which normally exists in HTML or XML format. Once the code is extracted, it is parsed (broken down into smaller parts), allowing it to identify and extract the predefined elements or objects such as classes, ratings, and tags.

Locally Saving the Data

After server access, code extraction, and parsing, information is stored in a structured format (either .csv or .xls) for easier access. The obtained data can now be freely analyzed or manipulated. 

Note that the above processes happen repeatedly. Be wary of issues such as excessive HTTP requests (occasioned by poorly coded proxies) and site crashing.

Step-by-Step Guide to Web Scraping

Identifying the Right URLs

The first step is to find the right URLs for the data you want. For example, you can obtain relevant data from sites such as, hotwire, and Orbitz if you are investigating hotel prices.

Page Inspection

The next step is to inspect the page before coding your web scraper to identify if there is anything relevant. All you need to do is right-click anywhere on the page and select ‘view page source’ or ‘inspect element’ to reveal the backend code for the scraper to read.

Identifying  the Relevant Data

This third step is to identify the data location in the backend code. Make sure you identify the unique tags that nest the content you need.

Writing the Necessary Code

After finding the proper nest tags, code them in your preferred scraping software using Python libraries. Remember to specify the exact data to be parsed and stored.

Code Execution

The fifth step is to execute the code, which directs the scraper to request site access and extract and parse data.

Store the Data

The last step is to store the data once it’s extracted, parsed, and collected, which you don’t have to do manually. Add extra lines to your code, and the algorithm will do all the work. Excel is one of the most common formats to use for data storage, even though there are several options to choose from.

Web Scraping Tips

Here are a few tips that can help you successfully gather the information you need from multiple web sources:

Refine Your Target Data

Be as specific as possible about the information you want to avoid ending up with lots of unnecessary data.

Check the Site’s Terms of Service

Review the site’s terms of service to understand your limits regarding the site’s data usage and avoid getting yourself in unnecessary trouble.

Follow All the Data Protection Protocols

Consider the laws in different jurisdictions, including their data protection protocols, when obtaining data from different websites. Some regions, such as the European Union, forbid the extraction of specific personal data, a provision you must abide by.


Web scraping guarantees information collection from different data sources. It has several uses, such as testing and training of machine learning methods. Remember to check the terms of service of web pages and the data protection protocols of different jurisdictions to avoid landing into trouble.