by Semalt Writer
Web scraping is an effective way of collecting information from the internet.
The web harvesting software accesses the World Wide Web using the Hypertext Transfer Protocol, collects data from different sites, and transforms it into a readable and scalable form.
Bots play a significant role in data collection and extraction. They help save scraped content in a centralized database for offline uses.
Web pages are built using different programming languages such as HTML and XHTML.
That is why, companies have developed various web scraping systems and rely on DOM parsing, computer vision, and natural language processing to simulate the human behavior.
Data scraping is considered to be an ad hoc and inelegant technique, but it is useful for enterprises, programmers, non-coders, webmasters, journalists, digital marketers and freelance writers.
A web scraper is an API that helps extract information from various sites. Companies like Google and Amazon provide different web scraping services and tools.
The latest forms of web scraping are data feeds, RSS feeds, Twitter feeds, and ATOM feeds. JSON and CSV are used as a transport storage mechanism between web servers and client.
Octoparse, Import.io, Kimono Labs and ParseHub are the most famous web scraping tools. They come both in free and paid versions and can accomplish a number of tasks for you.
Once downloaded and installed, these tools can scrape hundreds of web pages in an hour.
Top 10 Python libraries for web scraping:
Python is a high-level programming language. It features a dynamic system and automatic memory management.
Python supports different programming paradigms, such as object-oriented, functional, procedural and imperative.
It has a large number of standard libraries, but the most famous Python libraries are described below.
Requests is a Python HTTP library that focuses on the interaction of different websites.
It can manage cookies, keep track of logged-in sessions, and handle sites that are down or take a long time to respond.
It is licensed by the Apache2 License, and the goal of Requests is to send HTTP requests in a friendly and comprehensive way.
Scrapy is a web scraping software that helps extract useful information from different websites.
SQLAlchemy is a database library that is useful for programmers and web developers.
This HTML and XML parsing library is useful for freelancers and webmasters.
It is a tool for working with XML and HTML documents. It helps evaluate XPath and CSS selectors and find matching elements on the net.
This Python library helps accomplish tasks of 2D game development.
It is a powerful 3D animation and game creation engine, which is famous for its user-friendly interface.
8. Nltk (Natural Language Toolkit)
It helps manipulate different strings and can perform multiple tasks at a time.
Nose is a testing framework for Python used by hundreds of programmers all over the world.
With SymPy, you can perform multiple tasks and evaluate the quality of your web content.