What is Web Cache

Web cache works invisibly in your browser. It can speed up web surfing by storing info on sites you have visited previously.

Here are some of the things you need to know about what it is and how it works.

There are a number of elements that may impact speed when browsing the internet. Some of those factors are external, such as the available bandwidth and speed of your internet plan.

Some speed-impacting factors can be internal to your device.

One of these potential factors is called ‘web cache’ (you may know this as called ‘HTTP cache’ or just ‘cache’). This is designed to work invisibly to help speed up web surfing.

Web cache is designed as an invisible convenience. It should reduce loading times when revisiting webpages.

When you visit a website for the first time on a device there is something very particular that happens. The browser you are using downloads all the appropriate resources to ‘load up’ the webpage. These include things such as text, images, etc.

Web cache helps to speed up subsequent visits by avoiding the need to re-download some of those resources. The next time you load that same page, or load a new page on the same website (think of a persistent logo image) to load existing info.

Your computer storing this info helps to speed up loading times by reducing the perceived lag. It decreases the load on the web server (which hosts the website/s we visit), and reduces bandwidth usage.

This is how web cache reduces the loading times of previously visited webpage. In comparison to the first visit to a webpage, which had not been cached before it is much quicker.

Where is it stored?

The web cache itself is stored on your machine that you are using to browse. The data is stored on a per-browser basis.

So imagine, you visit our website using the Google Chrome browser on a laptop. You then visit it again using the Microsoft Edge browser on the same device. Your laptop would download and store the relevant cached data for both browsers.

Viewing your cached data

Most browsers will let you view your cached data.

For instance, if you use Google Chrome, you can type ‘chrome://cache’ into the URL bar to see a list of website items that have been cached.

The method for viewing cached data changes between browsers. If you’re interested, try a web search to find the method on your specific browser.

The use of web cached data reduces the need to re-download the same website data every time you revisit it.

Certain conditions have to be met for a browser to prioritise your cached resources over those stored on the website. Thi sis true even when revisiting. After all, your cached data might be out of date.

Web cache is measured and compared to the online resources it’s reflecting in terms of some key factors. These will include 'freshness' and 'validation'.

'Freshness' and 'validation' refer to a process that ensures your cached data is up to date with and reflective of what’s stored and displayed on the cached website.

If the cached data is out of date, it will be re-downloaded and updated in the locally stored web cache on a per-browser basis.

Downsides of web cache

Web cache is collected automatically and usually by default when you use a web browser.

Browsers tend to limit the amount of data they store as part of the downloaded web cache. This means that each browser will automatically delete old data to keep the web cache at a manageable size.

Anyone who has access to the same connected device and its web browsers also has access to your browsing history via cache.

Web cache can be erased on your browsers by using the ‘erase private browsing data’ function.

Remember, cache is only viewable for people who have direct access to your device, such as a shared computer. Web cache and web cookies both operate in the background within browsers as we surf the web. They serve very different functions.

Web cookies are used to store information that relates to user information. They may be used to offer personalised browsing or advertising.

Web cache is used to store resource files client-side on a device, unless manually removed by a user, to speed up the browsing process.

Web cache is useful for automatically speeding up the responsiveness of the websites we regularly visit. It is worth looking into manually clearing web cache at regular intervals.