Every time a user loads a web page, the search engine must download a large amount of data to be able to display the page. In order to shorten these loading times, search engines store or reserve most of the content that appears on the page, saving a copy of the content on the device's hard drive. These files are stored until their lifetime expires, or reserve storage space is exhausted.
Another aspect to note is that data in a cache is generally stored in fast access hardware such as RAM (Random-access memory) and can be used in correlation with a software component. A cache's primary purpose is to increase data retrieval performance by reducing the need to access the underlying slower storage layer.
In general, a cache stores data temporarily when it trades capacity for speed, unlike databases that often store data completely and durably.
The advantage of this reserve storage is that the next time the same page is loaded, most of the content will be already stored locally, and the page will load much faster.
A content delivery network is a group of geographically distributed servers that work together to provide fast delivery of content from the Internet.
On the other hand, we have DNS storage, which is a record of the websites that have been visited. When you want to access a website from the browser, this record will be the first site where it will be searched.
This also translates into a reduction in bandwidth costs, as well as an improvement in the user experience.
we can summarize the advantages of caching advantages in the following sentences:
When websites respond to CDN servers with the required content, the useful lifetime is also attached, indicating to the server how long it will store it. The lifetime is stored in the HTTP header, and specifies how long the content will be stored. When the time ends or expires, the content is removed. Some CDNs also remove content earlier if it is not requested for a period of time.