Data feed is a mechanism for users to receive updated data from data sources. It is commonly used by real-time applications in point-to-point settings as well as on the World Wide Web. The latter is also called web feed. News feed is a popular form of web feed. RSS feed makes dissemination of blogs easy. Product feeds play increasingly important role in e-commerce and internet marketing, as well as news distribution, financial markets, and cybersecurity. Data feeds usually require structured data that include different labelled fields, such as “title” or “product”.