give a brief description on internet book shops and grocery
Online shopping Online stores typically enable shoppers to use "search" features to find specific models, brands or items. Online customers must have access to the Internet and a valid method of payment in order to complete a transaction, such as a credit card, an Interac-enabled debit card, or a service such as PayPal. For physical products (e.g., paperback books or clothes), the e-tailer ships the products to the customer; for digital products, such as digital audio files of songs or software, the e-tailer typically sends the file to the customer over the Internet. The largest of these online retailing corporations are Alibaba, Amazon.com, and eBay.[1]
Index (publishing) In books, indexes are usually placed near the end (this is commonly known as "BoB" or back-of-book indexing). They complement the table of contents by enabling access to information by specific subject, whereas contents listings enable access through broad divisions of the text arranged in the order they occur. It has been remarked that, while "[a]t first glance the driest part of the book, on closer inspection the index may provide both interest and amusement from time to time."[8]