search engines can perform date-filtered searches because, when web servers send a webpage to a they include a header that contains information about the webpage, such as the date it was last modified.

Client

Explanation:

Servers responsibility is to send the appropriate page to the client through a protocol such as HTTP by evaluating the page url to see which page is to sent.They add some meta data into the headers of page that can be used by search engines for use.

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