What Is A Cache?
A cache is usually any type of intermediate storage (or “buffer storage”), for example, on the PC, a browser, or server. This type of buffer memory enables faster access to data that is called up frequently or at short notice (e.g., login data) without this data having to be reloaded for each call. This saving process often runs in the background and is overlooked by the user.
Cache in the Browser
A browser’s is usually a fast and large memory that stores the basic content of a website on the computer. The user cannot easily see which content he is holding. The cache is, so to speak, the short-term memory of a browser. The computer can access it more quickly than the regular working memory (RAM).
An example: You are visiting a website with extensive page content. Your browser, e.g., Firefox, Opera, or Safari, saves some of the website’s main content on your computer or smartphone. If you return to the website later in time or in a new session, the browser loads the stored content. The website builds up faster, and the loading time is shorten.
Cache on Search Engines like Google
A search engine such as Google also has its SERPs. This has several functions. Furthermore, the search engine temporarily stores the content of all web pages that search engine users consider for queries. Using a cached index, the search engine server searches for the most appropriate and up-to-date web content that is appropriate to answer the search query. This is the only way for the search engine to guarantee that results relevant to user input are display in fractions of a second.
Searching for information by Crawlers
A crawler takes over the independent search for content on the Internet. Google regularly crawls a website. At Google, this web crawler frequency is usually between one and four weeks. After each crawl, Google saves the status of the website in the cache. If your page is temporarily unavailable (due to a server error or an error in the CMS), the version saved in the cache is displayed. This version can be called up in the SERPs by clicking on the green triangle next to the URL:
Importance of the cache for Search Engine Optimization
Caching has disadvantages for websites that are update very often. Here there is the option of preventing caching with the meta tag “No-Cache” in the website code. A website can also give the crawler an indication of how frequently changes generally take place.
Alternatively, a website owner who recently made changes to their web pages can report them to Google. Soon a web crawler will read the content again and update it in the cache.
The information that is provided from the cache via a website often reveals whether the search engine operator has made changes to your algorithm. Search engine optimizers can take the findings from this into account when further optimizing the website.
When should you clear the Cache?
After a certain amount of time, the cache of a browser, program, or server may store too much information. This can slow down the computer or smartphone. In this case, it is worth clearing the cache memory. Once you have cleared your cache, you must expect to log in again on all the pages you have visited. If you want to make your traces in the browser unrecognizable to a certain extent, you should also delete your cache regularly.