• Web Scraper Meaning
• What Is Web-scraping
• What Does Web Scraping Mean
• Web Scraper Meaning
• Web Scrape Meaning

• Python Web Scraping Tutorial

• Python Web Scraping Resources

Web scraping is a term for various methods used to collect information from across the Internet. Generally, this is done with software that simulates human Web surfing to collect specified bits of information from different websites. Web scraping is an automated method used to extract large amounts of data from websites. The data on the websites are unstructured. Web scraping helps collect these unstructured data and store it in a structured form. There are different ways to scrape websites such as online Services, APIs or writing your own code. Web data scraping, also known as web data extraction, is the process of retrieving or “scraping” data from a website. Unlike the mundane, mind-numbing process of manually extracting data, web scraping uses intelligent automation to retrieve hundreds, millions, or even billions of data points from the internet’s seemingly endless frontier.

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Web scraping is an automatic process of extracting information from web. This chapter will give you an in-depth idea of web scraping, its comparison with web crawling, and why you should opt for web scraping. You will also learn about the components and working of a web scraper.

What is Web Scraping?

The dictionary meaning of word ‘Scrapping’ implies getting something from the web. Here two questions arise: What we can get from the web and How to get that.

The answer to the first question is ‘data’. Data is indispensable for any programmer and the basic requirement of every programming project is the large amount of useful data.

The answer to the second question is a bit tricky, because there are lots of ways to get data. In general, we may get data from a database or data file and other sources. But what if we need large amount of data that is available online? One way to get such kind of data is to manually search (clicking away in a web browser) and save (copy-pasting into a spreadsheet or file) the required data. This method is quite tedious and time consuming. Another way to get such data is using web scraping.

Web scraping, also called web data mining or web harvesting, is the process of constructing an agent which can extract, parse, download and organize useful information from the web automatically. In other words, we can say that instead of manually saving the data from websites, the web scraping software will automatically load and extract data from multiple websites as per our requirement.

Origin of Web Scraping

The origin of web scraping is screen scrapping, which was used to integrate non-web based applications or native windows applications. Originally screen scraping was used prior to the wide use of World Wide Web (WWW), but it could not scale up WWW expanded. This made it necessary to automate the approach of screen scraping and the technique called ‘Web Scraping’ came into existence.

Web Crawling v/s Web Scraping

The terms Web Crawling and Scraping are often used interchangeably as the basic concept of them is to extract data. However, they are different from each other. We can understand the basic difference from their definitions.

Web crawling is basically used to index the information on the page using bots aka crawlers. It is also called indexing. On the hand, web scraping is an automated way of extracting the information using bots aka scrapers. It is also called data extraction.

To understand the difference between these two terms, let us look into the comparison table given hereunder −

Uses of Web Scraping

The uses and reasons for using web scraping are as endless as the uses of the World Wide Web. Web scrapers can do anything like ordering online food, scanning online shopping website for you and buying ticket of a match the moment they are available etc. just like a human can do. Some of the important uses of web scraping are discussed here −

• E-commerce Websites − Web scrapers can collect the data specially related to the price of a specific product from various e-commerce websites for their comparison.

• Content Aggregators − Web scraping is used widely by content aggregators like news aggregators and job aggregators for providing updated data to their users.

• Marketing and Sales Campaigns − Web scrapers can be used to get the data like emails, phone number etc. for sales and marketing campaigns.

• Search Engine Optimization (SEO) − Web scraping is widely used by SEO tools like SEMRush, Majestic etc. to tell business how they rank for search keywords that matter to them.

• Data for Machine Learning Projects − Retrieval of data for machine learning projects depends upon web scraping.

Data for Research − Researchers can collect useful data for the purpose of their research work by saving their time by this automated process.

Components of a Web Scraper

A web scraper consists of the following components −

Web Crawler Module

A very necessary component of web scraper, web crawler module, is used to navigate the target website by making HTTP or HTTPS request to the URLs. The crawler downloads the unstructured data (HTML contents) and passes it to extractor, the next module.

Extractor

The extractor processes the fetched HTML content and extracts the data into semistructured format. This is also called as a parser module and uses different parsing techniques like Regular expression, HTML Parsing, DOM parsing or Artificial Intelligence for its functioning.

Data Transformation and Cleaning Module

The data extracted above is not suitable for ready use. It must pass through some cleaning module so that we can use it. The methods like String manipulation or regular expression can be used for this purpose. Note that extraction and transformation can be performed in a single step also.

Storage Module

After extracting the data, we need to store it as per our requirement. The storage module will output the data in a standard format that can be stored in a database or JSON or CSV format.

Working of a Web Scraper

Web scraper may be defined as a software or script used to download the contents of multiple web pages and extracting data from it.

We can understand the working of a web scraper in simple steps as shown in the diagram given above.

Step 1: Downloading Contents from Web Pages

In this step, a web scraper will download the requested contents from multiple web pages.

Step 2: Extracting Data

The data on websites is HTML and mostly unstructured. Hence, in this step, web scraper will parse and extract structured data from the downloaded contents.

Web Scraper Meaning

Step 3: Storing the Data

Here, a web scraper will store and save the extracted data in any of the format like CSV,JSON or in database.

Step 4: Analyzing the Data

After all these steps are successfully done, the web scraper will analyze the data thus obtained.

Some websites can contain a very large amount of invaluable data.

Stock prices, product details, sports stats, company contacts, you name it.

If you wanted to access this information, you’d either have to use whatever format the website uses or copy-paste the information manually into a new document. Here’s where web scraping can help.

What is Web Scraping?

Web scraping refers to the extraction of data from a website. This information is collected and then exported into a format that is more useful for the user. Be it a spreadsheet or an API.

Although web scraping can be done manually, in most cases, automated tools are preferred when scraping web data as they can be less costly and work at a faster rate.

But in most cases, web scraping is not a simple task. Websites come in many shapes and forms, as a result, web scrapers vary in functionality and features.

If you want to find the best web scraper for your project, make sure to read on.

How do Web Scrapers Work?

Automated web scrapers work in a rather simple but also complex way. After all, websites are built for humans to understand, not machines.

First, the web scraper will be given one or more URLs to load before scraping. The scraper then loads the entire HTML code for the page in question. More advanced scrapers will render the entire website, including CSS and Javascript elements.

Then the scraper will either extract all the data on the page or specific data selected by the user before the project is run.

Ideally, the user will go through the process of selecting the specific data they want from the page. For example, you might want to scrape an Amazon product page for prices and models but are not necessarily interested in product reviews.

Lastly, the web scraper will output all the data that has been collected into a format that is more useful to the user.

Most web scrapers will output data to a CSV or Excel spreadsheet, while more advanced scrapers will support other formats such as JSON which can be used for an API.

What Is Web-scraping

What Kind of Web Scrapers are There?

Web scrapers can drastically differ from each other on a case-by-case basis.

For simplicity’s sake, we will break down some of these aspects into 4 categories. Of course, there are more intricacies at play when comparing web scrapers.

• self-built or pre-built
• browser extension vs software
• User interface
• Cloud vs Local

Self-built or Pre-built

Just like how anyone can build a website, anyone can build their own web scraper.

What Does Web Scraping Mean

However, the tools available to build your own web scraper still require some advanced programming knowledge. The scope of this knowledge also increases with the number of features you’d like your scraper to have.

Web Scraper Meaning

On the other hand, there are numerous pre-built web scrapers that you can download and run right away. Some of these will also have advanced options added such as scrape scheduling, JSON and Google Sheets exports and more.

Browser extension vs Software

In general terms, web scrapers come in two forms: browser extensions or computer software.

Browser extensions are app-like programs that can be added onto your browser such as Google Chrome or Firefox. Some popular browser extensions include themes, ad blockers, messaging extensions and more.

Web scraping extensions have the benefit of being simpler to run and being integrated right into your browser.

However, these extensions are usually limited by living in your browser. Meaning that any advanced features that would have to occur outside of the browser would be impossible to implement. For example, IP Rotations would not be possible in this kind of extension.

On the other hand, you will have actual web scraping software that can be downloaded and installed on your computer. While these are a bit less convenient than browser extensions, they make up for it in advanced features that are not limited by what your browser can and cannot do.

User Interface

The user interface between web scrapers can vary quite extremely.

For example, some web scraping tools will run with a minimal UI and a command line. Some users might find this unintuitive or confusing.

On the other hand, some web scrapers will have a full-fledged UI where the website is fully rendered for the user to just click on the data they want to scrape. These web scrapers are usually easier to work with for most people with limited technical knowledge.

Some scrapers will go as far as integrating help tips and suggestions through their UI to make sure the user understands each feature that the software offers.

Cloud vs Local

From where does your web scraper actually do its job?

Local web scrapers will run on your computer using its resources and internet connection. This means that if your web scraper has a high usage of CPU or RAM, your computer might become quite slow while your scrape runs. With long scraping tasks, this could put your computer out of commission for hours.

Web Scrape Meaning

Additionally, if your scraper is set to run on a large number of URLs (such as product pages), it can have an impact on your ISP’s data caps.

Cloud-based web scrapers run on an off-site server which is usually provided by the company who developed the scraper itself. This means that your computer’s resources are freed up while your scraper runs and gathers data. You can then work on other tasks and be notified later once your scrape is ready to be exported.

This also allows for very easy integration of advanced features such as IP rotation, which can prevent your scraper from getting blocked from major websites due to their scraping activity.

What are Web Scrapers Used For?

By this point, you can probably think of several different ways in which web scrapers can be used. We’ve put some of the most common ones below (plus a few unique ones).

• Scraping site data before a website migration
• Scraping financial data for market research and insights

The list of things you can do with web scraping is almost endless. After all, it is all about what you can do with the data you’ve collected and how valuable you can make it.

Read our Beginner's guide to web scraping to start learning how to scrape any website!

The Best Web Scraper

So, now that you know the basics of web scraping, you’re probably wondering what is the best web scraper for you?

The obvious answer is that it depends.

The more you know about your scraping needs, the better of an idea you will have about what’s the best web scraper for you. However, that did not stop us from writing our guide on what makes the Best Web Scraper.

Of course, we would always recommend ParseHub. Not only can it be downloaded for FREE but it comes with an incredibly powerful suite of features which we reviewed in this article. Including a friendly UI, cloud-based scrapping, awesome customer support and more.

Want to become an expert on Web Scraping for Free? Take ourfree web scraping courses and become Certified in Web Scraping today!