Web Scraping: How the Technology Works

By Sony T
13 Min Read
Web Scraping: How the Technology Works 1

You have probably heard of web scraping and its significance in helping company owners get insights from the information accessible on the internet. Web scraping is a great way to gather data, but the quality and insights you get will depend on the web scraping technology you choose.


In this article, we will look at web scraping, scraping tools, how scrapers work, types of web scrapers, and the technologies used to scrape.

What is Web Scraping?

Web scraping is an automated process for obtaining vast amounts of data from websites. Data in HTML is mostly unstructured before being transformed into spreadsheet or database format for further usage in different applications. Web scraping can be done in various ways, and each has its advantages and disadvantages.

For example, you might use web services or APIs or write your own web scraping programs from the ground up. Using APIs, it is possible to access structured data from many of the world’s most popular websites, such as Google, StackOverflow, and Twitter.

It is the best choice. However, many other sites do not enable users to access significant volumes of structured data or are less technologically sophisticated than this one. Web scraping is the best method for obtaining data from a website in this case.

A crawler and a scraper are needed for web scraping. To find the needed information, the crawler follows the links on the internet and scans for relevant content.

A scraper is designed to do just that when extracting data from the internet. The scraper’s architecture might vary greatly depending on the project’s complexity and breadth so that data can be extracted quickly and precisely.

The Basics of Web Scraping

It is a two-step process consisting of a web crawler and a scraper. While the scraper follows the crawler like a guide, the scraper extracts the data it needs.


When it comes to web crawlers, we call them “spiders”. They are artificially intelligent machines that use links and exploration to find and index material on the internet. Often, to find URLs for your scraper, you must first “crawl” the web or a single page to find it.


Using a web scraper, you can rapidly and precisely gather data from a website. To discover the data, you want to scrape from an HTML file, you need to utilize data locators, such as CSS selectors, XPath, regex, or any combination of these.

Different Types of Web Scrapers

Web scrapers can be classified as self-built or pre-built, browser extensions or software, and cloud or local.

Custom Web Scrapers

The custom scraper enables you to swiftly extract data from thousands of URLs using a single command-line interface. With this method, you can extract data from any rendered sources, even anything that is not shown in the browser. You can customize and make your scraper or get help from custom data solution experts to provide you with a custom scraper that meets your requirements.

Browser Extensions Web Scrapers 

Browser extension web scrapers allow you to gather data from the internet. It is simple to use since it is incorporated into your browser, but this also constrains it. Web scrapers do not support any functionalities beyond your browser’s capabilities.

Cloud Web Scrapers

Web scrapers that operate in the cloud or on an off-site server are known as cloud web scrapers. Using these can free up resources on your computer, allowing it to do other duties. As a result, it does not take a lot of computing power to extract data from websites.

Local Web Scrapers

On the other hand, local web scrapers operate on your computer and use your resources. Therefore, your computer will become sluggish and unusable if the web scrapers need additional processing power or memory.

Pre-built Web Scrapers

On the other hand, web scrapers are pre-built scrapers that can be downloaded and launched quickly. You can also edit them with more complex features.

Self-built Web Scrapers

Self-built web scrapers are possible, but they need a high level of programming expertise. Therefore, you will need to learn much more if you want an advanced web scraper.

Software Web Scrapers 

However, since they can be downloaded and installed on your computer, these restrictions do not apply to software web scrapers. Browser web scrapers are simpler, but they are not. There are also sophisticated functions that limit your browser’s limitations.

How Do Web Scrapers Work?

All of the information on a given website, or only the information a user desires, can be scraped using web scrapers. Ideally, you should describe what data you want the web scraper to retrieve so that it can extract that data fast and efficiently.

To use a web scraper, the URLs must first be given. As a result, it downloads all of the websites’ HTML code and the CSS and JavaScript parts.

This HTML code is parsed by the scraper, which then produces the desired data in the format requested by the user. However, data can be stored in different formats, such as a JSON file and more traditional spreadsheet and CSV file formats.

What is a Scraping Tool?

A web scraping tool is a piece of software created expressly to extract (or “scrape”) valuable data from websites. If you gather data from websites in a programmed way, you will probably be using a scraping tool.

When using a scraping tool, HTTP requests are sent to a target website, and the data on the page is extracted. As a general rule, it parses publicly available material and is visible to the public and displayed as HTML by the server. APIs (application programming interfaces) can also get additional information from a database, such as product pricing or contact information, and transmit it to a browser through HTTP queries.

Web scraping technologies come in many varieties, each with a unique set of features that can be tailored to meet the needs of a particular extraction job. A scraping program that can detect the unique HTML site structure or extract, reformat, and save data from APIs, for example, can be required.

It is possible to utilize general-purpose programming libraries and combine them to construct a scraper. Scraping tools might be big frameworks developed for all sorts of everyday tasks.

To scrape data from your website, you can use an HTTP requests library, such as Python-Requests, in conjunction with Python BeautifulSoup. It is also possible to build your HTTP client and HTML parser framework. Scrapy is a well-known open-source library designed to handle more complex scraping tasks.

Web Scraping Technologies

Here are a few web scraping technologies that help gather and extract data according to user demands.


BoilerPipe is an excellent choice for extracting clean text and any accompanying titles. Structured or unstructured data can both be extracted using BoilerPipe’s Java library. It removes superfluous HTML tags and other page clutter intelligently.

Boilerpipe’s main selling point is its speed and ease of extracting essential data from large amounts of unstructured data. The high level of precision makes it one of the most straightforward techniques for extracting data. As a result, you can improve your web scraping abilities right away if you learn how to use this program.


Celerity is a JRuby wrapper for HtmlUnit, a headless Java browser that supports JavaScript. It provides an easy-to-use API for navigating online apps programmatically. It is swift because no time-consuming GUI rendering or extraneous downloads are required. It runs quietly after the initial setup, is expandable, and does not take much space. Scraping and crawling the web is quick and effective with Celerity.


Nutch is widely regarded as the gold standard in web scraping technology. An open-source web crawler application is all there is to it. Data can be retrieved and stored using Nutch after being programmed to meet the project’s requirements. Scraping and crawling with this tool is easy because of the sophisticated algorithm.

Scraping requires hand-coding the web pages to be crawled and data extracted into Nutch. Once it was set up, it would scan over the list of pages and get the necessary information from the server. However, it is possible to learn a few basic scraping instructions using Nutch, which will make the process simpler. If you are interested in learning how to scrape the web, Nutch should be at the top of your to-do list.


Selenium is a web browser automation tool that can do various operations on autopilot. Selenium is an excellent tool for learning about how websites function. In other words, it can act how a human visitor to a website using a standard web browser would act. As a result, it can get the same data that a human visitor would see on the website.

It is often used in web scraping to mimic ajax requests. In addition to web scraping, Selenium can assist you with testing websites and automating any time-consuming process related to the internet. It is possible to become a web scraping expert by understanding Selenium.


Watir is a Ruby library family that can automate web browsers. I like that it is simple to set up and utilize. This bot can achieve human-like interaction with the browser.

Watir can do whatever a person would do on a web page, including clicking links, filling out forms, hitting buttons, and so forth. Watir is a pleasure to use and set up because of Ruby’s awesomeness. Reading and writing spreadsheets and XML documents are just some of the things you can do using Ruby’s programming language.


Web scraping is becoming more popular because it provides company owners and others easy access to tons of valuable information. However, extracting it successfully and obtaining reliable data is not easy. Therefore, you must use the most effective web scraping strategies and technologies.

Web scrapers make extracting and sorting datasets easier, regardless of whether you use a pre-built or custom-built solution. It is the era of data, and whoever uses it to improve their business and increase their revenue is totally up to them. Good Luck!

Share This Article
By Sony T
Sony is a passionate bloggers writes on Futuristic technologies ...