A good example of web crawling can be bookswebsite.com (Example). It is a famous site with loads of content, let’s suppose that person A wanted to list down all the books that bookswebsite has under the comedy category. Person A wants the data in the excel format. Now he goes to bookswebsite and types in the keyword comedy under the book category. Person A sees a over a million results. Now if he starts entering the information in the excel sheet manually, it will take a lot of time and effort (probably months).
However with Web Crawling, this task can be done easily. The web crawler bot goes to the website searches books category and then enters all of the relevant information in the excel file that Person A wants. The tasks which was probably going to take months of efforts can now be done via robot effortlessly.