Cookies and cache (or browser cache) are two forms of temporary storage kept on client’s machine to improve the performance of web pages. Cookie is a very small piece of information that is stored on the client’s machine by the web site and is sent back to the server each time a page is requested. Cache is a temporary storage of web page resources stored on client’s machine for quicker loading of the web pages.
Cookies are used to store information. It is also known as HTTP cookie, web cookie, or browser cookie. It is basically a small file which a web server sends to the PC. It happens automatically when someone browses certain web sites. These cookies help in the identification of the user. For example, a login detail gets stored in a cookie. Next time when the same user visits the same website, re-entering the information of log-in details is not required. This information is in the form of a string comprising of letters and numbers. It is helpful in session management and tracking. Cookies was first introduced by Netscape and in those earlier stages cookies did not receive good acceptance, since rumours said it might hack your personal data. Later people realised that cookies are actually harmless, and now they are highly accepted. Cookies are usually used to store information needed for shorter periods. At the end of this, a cookie becomes expired.
Cache is a temporary storage that stores elements of a web page, especially those which might be required later. It could be any element like a graphic file, script file, etc. The information is automatically downloaded at the browser’s cache on the loading of a web page. It helps in faster rendering of the same page next time. It saves the time of the user as well as of the network. One can also change the size of the cache. However, this change would depend upon the particular browser.
Similarities and Differences
Although cookies and cache are two ways to store data on client’s machine, they serve different purposes:
- A cookie is used to store information. It is basically a small file which a web server sends to the PC. It happens automatically when someone browses certain web sites. Cache is also a temporary storage that stores the web page element, especially those which might be required later. It could be any element like a graphic file, script file, etc;
- A cookie is used to store information to track different characteristics related to user, while cache is used to make the loading of web pages faster;
- A cookie stores information such as user preferences, while cache will keep resource files such as audio, video or flash files;
- A cookie expire after some time, but cache is kept in the client’s machine until they are removed manually by the user.
I hope that this article helped you to understand what is the difference between Cookies and Cache. Feel free to share your thoughts about this article using the comments section below or catch us on Twitter.