Web scraping involves retrieving texts from web pages. It is more efficient than old-fashioned cutting and pasting and lifts the HTML code rather than just the page’s surface. Web scraping is often used for marketing research and website development.
How Does Web Scraping Work
Web scraping involves two phases–web crawling and the actual scraping. The crawler searches the internet for links to materials you want to scrape. Once the links are located, a scraper retrieves the code from the page and can lift millions of data points if needed. There are various web scraping techniques, and each has unique advantages.
HTML Parsing
HTML parsing is the processing of the retrieved HTML. A parser will take a piece of code and transform it into something that a computer can actually use. Parsing tools will remove HTML tags and decode entities. It will also check the editing and will fill in replacement text where needed.
In addition to dealing with the code once it has been scraped, parsing can also be a method of actual web scraping. This method uses JavaScript and focuses on nested or linear HTML pages. This is a quick way to lift texts and resources.
DOM Parsing
Another form of parsing that is also used for web scraping is DOM parsing. DOM stands for Document Object Model, which defines the structure of XML files. It involves embedding a browser such as Mozilla Firefox or Internet Explorer to lift dynamic pages. DOM parsers create an image of a page’s layout, and scrapers can retrieve the data.
Vertical Aggregation
Vertical aggregation is the process by which companies develop platforms that monitor bots for specific verticals. Through this method, knowledge is applied to an entire vertical and automates the generation of new media. The platforms create new bots and monitor verticals. The type of bot is measured by the kind of data they extract.
Google Sheets
Many scrapers involve coding or special tools, but you can also scrape a web page from Google Sheets. This process involves locating the text on a web page and using the IMPORT XML function to retrieve the content. This method is relatively simple, but it only works if there is a specific structure to the content.
XPath
XPath uses path expressions for the selection of nodes in an XML document. It is a way to zero in on an XML element without searching through the whole HTML tree. To scrape using this method, it is essential to have basic knowledge of XPath expressions. It can be used together with DOM methods and can navigate them. XPath can create a match for text within HTML elements. XPath can also be used together with programs like Python for web scraping.
Text Pattern Matching
This method uses a regular expression or a series of characters that comprise a search pattern with string matching ( or search and replace operations). These regular expressions can match tags and extract HTML text. This can be done because HTML is composed of strings, and when a text matches these strings, it can be useful for lifting data. Although this system can be imperfect because of occasional mismatched tags, text pattern matching can help you locate the scraping text.
Benefits of Web Scraping
There are many benefits to web scraping. This method is ideal for research purposes and marketing. Lifting texts from competitor websites provide insight into content strategy and keyword research. Having the right keywords can drive traffic to your site, and web scraping is essential for researching your rival’s keywords and SEO strategy.
Also, web scraping retrieves information from social media pages and reviews of your products. It is essential to know what people are saying about your brand on the internet. Automated web scraping supplies information on an ongoing basis with customer feedback that can be useful for data analytics, marketing, and product development.
Lead generation is a challenge for any business. Pre-designed lists do not often contain quality leads, and while lead generation tools are efficient, they tend to come with hefty price tags. Web scraping can generate leads through niche websites that match the information of your customer persona, including education, jobs, and business. This is a quick way to retrieve a large number of leads from all over the web.
Taking the Guesswork out of Web Scraping
Web scraping provides valuable information for research or marketing, and there are many ways to retrieve texts from websites. Some methods require coding whereas others demand no technical knowledge. Trying a variety of scraping techniques can help you decide which one is right for you.
