Web Scraping vs. Web Crawling – Film Daily
People often use web scraping and web crawling interchangeably, but they are far from the same. Both are data collection processes, but there are significant differences between them.
So what is a web crawler and how is it different from a web scraper? Let’s find out.
Definition of web scraping
Web Recovery or web harvesting is the automated process of extracting data from websites. You can use it to download specific data like product details and pricing information from a target website.
In simple terms, this means copying the data you need before using various tools to analyze it. You can import it into a spreadsheet or internal database and integrate the storage location with the desired analysis tool for processing.
Definition of web crawling
Web crawling is the process of analyzing websites to index them and help users find relevant content quickly. Besides search engines, website owners rely on web crawlers to scan their pages for potential errors like broken links and duplicates and update their content.
what is a crawler? It is an online crawler, also known as a spider bot, that crawls website pages to index them based on keywords, links, meta tags, HTML text, content relevance, etc. . here is some research this takes the subject of web crawlers even further.
Web crawlers help search engines display relevant content in search results and play a role in SEO rankings, helping Google and other search engines rank websites based on content information collected.
These processes may seem even more confusing now, as both have a role in data mining. Here’s how they are different.
Data collection and purpose
Web scraping downloads specific information from websites for further analysis using scraping software, while web crawling uses bots to read and store all data from a website.
Web scrapers send requests to the target URL, extract the HTML code, parse the data string to extract the relevant information, and download the data.
Web crawlers visit a URL from a specific seed set, retrieve the data, analyze the content, identify links to add to the border of the URL, index the page and move on to the next URL until the border is empty.
Data deduplication (filtering out duplicate data) is crucial for web crawling. This is not necessarily the case with scraping which does not include large amounts of data. Since you are using it to analyze specific data, you can manually filter out redundant information.
The Robot Exclusion Standard
The Robots Exclusion Standard (robots.txt protocol) tells crawlers which pages they can access and crawl. It is not a protocol for hiding pages from Google and other search engines; this is only possible by blocking indexing. This only helps to avoid unnecessary HTML requests that could overload a website.
Thus, most spider bots obey this standard, but most detection tools do not. This means that you can extract any information from a website, even when its robot.txt file tries to prevent it.
Advantages and disadvantages
These methods are advantageous but also have particular disadvantages. Here are the most notable ones to consider.
Benefits of web scraping
- Speed, accuracy and profitability — Web scrapers can extract data from multiple websites simultaneously at high speed. They are affordable and eliminate the need for additional staff.
- business intelligence — Data mining can help you conduct market research, analyze competition, optimize pricing strategies, and monitor industry trends and news to stay relevant.
- Brand Protection — Detecting ad fraud, trademark counterfeiting, counterfeit products and patent theft becomes child’s play with web scraping. You can improve brand, PR, and risk management seamlessly.
Disadvantages of web scraping
- Limited functionality — Web scrapers do not perform data analysis, so you need additional software to process and interpret the data.
- Regular maintenance — Websites are constantly changing, so you need to update your scraper regularly. Otherwise, it may provide inaccurate data or stop working.
- IP detection — Many websites block scrapers to avoid resource consumption. Others monitor their websites for IP addresses from specific countries to prevent or restrict access to their content. This means your scraper might get an IP ban, which is why you might want to use a proxy.
Benefits of web crawling
- Website improvement — A web crawler can help you analyze metadata, keywords and links. It can detect website errors such as broken links, incorrect URLs, page redirects, etc. This is a great tool for performing regular website audits for continuous improvement.
- SEO Optimization – Your website improvements can help you improve your SEO ranking, but you can also analyze the SEO of your competitors to improve your strategies.
Disadvantages of web crawling
- Indexing unstructured data — Spider bots index unstructured data, so you need other tools like web scrapers to convert it into structured data before parsing it for insights.
- IP blocks — Like scrapers, crawlers can get an IP ban, but a proxy can solve this problem.
Web crawling and web scraping are essential for collecting valuable data, but they are two different processes. The former helps you digitize and store large sets of data while the latter collects and converts specific information for further analysis. This is why using both might be the best option to maximize the result.