Web crawler (also known as web spider and web robot, and more often called web chaser in FOAF community) is a program or script that automatically crawls information on the World Wide Web according to certain rules. Other less common names are ant, automatic index, emulator or worm. The most common application of crawler technology is to obtain all kinds of information on the website, such as news, prices, comments and user information, which can be used for data analysis, big data application, public opinion monitoring, market research and so on.

With the rapid development of the network, the World Wide Web has become the carrier of a large amount of information, and how to effectively extract and use this information has become a huge challenge. Search engines, such as traditional general search engines AltaVista, Yahoo! As a tool to help people retrieve information, Google has become the entrance and guide for users to access the World Wide Web.

Application of reptile technology

1, Network Security: Crawler technology can scan network vulnerabilities, malware, etc. To help users protect their websites and data security.

2. Information monitoring: Obtaining relevant website information through crawler technology can realize real-time monitoring of keywords, competitors and industry trends, and provide enterprises with the latest market information and competitor trends.

3. Social networking: Using crawler technology, users' personal information, friends' relationships, published contents, etc. can be quickly obtained, providing more information and functions for social networking services, such as recommending friends and personalized advertisements.

4. Machine learning: Crawler technology can be used to collect a large amount of data, provide data sources for machine learning algorithms, and improve the accuracy and effect of the algorithms.