Web Scraping
In this article, you will learn about the advantages and differences between web crawling and web scraping. Learn how these methods are used to extract data from websites and gain insight into their applications.
What is data scraping?
Data is not always written in a form that is convenient to process. A simple example is a complex and unreadable website address on a manager's paper business card. It turns out that in order for the client to access this data (to convert it from a drawn form into a symbolic input inside the browser's address bar), letters, numbers and other symbols must be manually typed on the keyboard.
But the format can be changed by putting a QR code on the business card or using an NFC tag. Then the necessary information can be easily read using special programs like email scraping tools. And the user will not make a mistake, and the input process will be noticeably faster.
But the format can be changed by putting a QR code on the business card or using an NFC tag. Then the necessary information can be easily read using special programs. And the user will not make a mistake, and the input process will be noticeably faster.
Approximately the same situation occurs when the data being searched for, stored on the computer's hard drive, is actually in an "unreadable" form, that is, incompatible with programs. After all, each program is designed to read only those formats that its developers have provided. And if the existing formats are not supported, then the program will not be able to read the file.
Now another example: imagine that you need to collect a database of email addresses, but they are stored inside PDF files, images (photographs of business cards), an email client, in business documents, etc. How can you collect the necessary information in one place and at the same time convert it into a more convenient (readable) format?
A parser program (scraper) will help. It can open files of different types, find the necessary information in them and save the data in another format (usually in the form of tables or lists, but there may be other formats, such as XLM markup, etc.).
The process of searching for information and converting it into a new type/format is called parsing or scraping.
Previously we talked about what parsing is.
From the English word scraping - "scraping" or "scraping". As a result, we get the following definition.
Scraping is the process of searching and converting data into a more convenient format suitable for analysis, storage, indexing, etc.
What is Web Scraping?
Web scraping, as can be understood from the prefix "web", is the search and conversion into a convenient format of web data. That is, information posted on the pages of sites and services on the Internet.
Web scrapers are the most widespread. Why?
- With their help, you can quickly and massively check your sites for errors and the quality of content, for compliance with the structure, for the presence of mandatory tags, marks, etc.
- Web parsers can emulate user behavior, so with the help of software you can check the quality of a website/web service, its level of security, load and other characteristics.
- Scrapers allow you to quickly find the necessary information on a given topic on the Internet or on specific sites.
- With their help, you can structure and accumulate various data about competitors' websites. For example, monitor price dynamics, range of products, announcements of new promotions, etc. This is a powerful marketing and research tool.
- Scrapers can detect new content and notify about other types of events (negative reviews, new comments, special offers, mentions, etc.).
- With special software modules, scrapers can convert one data format to another. For example, they can scan images in search of text information (recognition function), etc.
Web scrapers can operate as standalone software on the user's equipment (on his PC or on a virtual/dedicated server), or deployed in the cloud (provided as a service, SaaS or PaaS format). In some cases, scrapers can be part of more complex software packages as one of the system elements.
The tasks and goals of web scrapers can be anything from positive, aimed at creation and improvement, to negative, aimed at industrial espionage, detection of security holes, etc.
The most popular tasks for business:
- Competitor analysis (marketing research).
- Monitoring prices and product range.
- Search for news and thematic content.
- Finding and extracting contact information.
- SEO tasks (search engine optimization).
- SERM tasks (online reputation management).
If the advantages of parsers/scrapers are more or less clear (they help in solving applied problems), then few people talk about the disadvantages. Let's correct this injustice.
What is the difference between Web Crawling and Web Scraping?
By martins10
What is the difference between Web Crawling and Web Scraping?
What is the difference between Web Crawling and Web Scraping?
- 61