Exploring the Different Types of Client-Side Cache and Their Benefits

Cache is pronounced cash. It is a temporary memory to store duplicate data that is originally stored elsewhere. Cache is used when the original data is expensive to fetch (due to longer access time) or to compute, compared top the cost of reading the cache.

Introduction

In web development, caching is the process of storing data or resources in a temporary location for quick access. Caching is widely used in client-side web development to improve the performance and reduce the load time of web applications or in other words caching is an essential technique that reduces network latency and improves page load times. Client-side caching can be achieved using different types of cache, each having its own benefits and limitations. In this response, I will explain the concepts and types of cache in client-side cache.

Concepts of Cache

Cache is a temporary storage location that stores frequently accessed data or resources to reduce the number of requests sent to the server. Caching helps to reduce the load time of web pages and improves the performance of web applications.

The following are the concepts of cache in client-side caching:

1. Cache Control: Cache Control is a HTTP header that controls caching behaviour. It is used to specify how long the data or resources should be cached, and when it should be re-fetched from the server. It includes directives like max-age, no-cache, and no-store.
2. Cache-ability: Cache-ability is the ability of a resource to be cached. Resources that are cacheable can be stored in the cache, while non-cacheable resources cannot be cached. Cache-ability depends on the cache control headers and the type of resource.
3. Cache Invalidation: Cache Invalidation is the process of removing the cached data or resources when they become stale or outdated. It is important to invalidate the cache to ensure that users see the latest version of the data or resources.
4. Cache Hit: When a requested resource is already stored in the cache, and the cache is able to return the resource to the client without requiring a network request, it’s called a cache hit.
5. Cache Miss: When a requested resource is not stored in the cache, and the cache is unable to return the resource to the client, it’s called a cache miss. In this case, the client must make a network request to fetch the resource from the server.

Types of Cache:

There are different types of cache used in client-side caching. The following are the types of cache in client-side caching:

1. Browser Cache: Browser cache is a type of cache used by web browsers to store frequently accessed data or resources. Browser cache stores resources like HTML pages, images, and scripts to reduce the load time of web pages. Browser cache can be controlled using cache control headers.

The browser cache has a maximum size limit, and once the limit is reached, the browser starts to remove the least recently used items from the cache.

1. Cookie Cache: Cookie cache is a type of cache used by web browsers to store cookies. Cookies are small text files that are used to store user information like login credentials and preferences. Cookie cache can be controlled using cookie expiration time.
2. Local Storage Cache: Local storage cache is a type of cache used by web applications to store data in the client’s browser. Local storage cache can be controlled using JavaScript. Local storage is useful for storing user preferences, such as language settings, and other user-specific data.

Unlike cookies, local storage is more persistent than browser cache and can store larger amounts of data and is not sent to the server with every request. Local storage is limited to 5–10MB, depending on the browser, and the data is stored until the user clears the browser cache or the website deletes the stored data.

4. Session Storage Cache: Session storage cache is similar to local storage cache but is used for storing data that is only relevant during the user’s session. When the user closes the browser or the session expires, the data is deleted.

Session storage is useful for storing temporary data such as form data or user inputs. Like local storage, session storage is limited to 5–10MB, depending on the browser.

5. Application Cache: Application cache is a type of cache used by web applications to store resources like HTML pages, images, and scripts. Application cache can be used to create offline web applications, where the user can access the web application even when there is no internet connection.

The application cache is stored separately from the browser cache, and the files specified in the manifest file are downloaded and stored in the application cache when the user first visits the website. When the user revisits the website, the browser checks the application cache to see if the files have been updated since the last visit. If there are any changes, the browser downloads the updated files and stores them in the application cache.

Conclusion

Caching is an important concept in web development, and client-side caching can be achieved using different types of cache. Each type of cache has its own benefits and limitations, and it is important to choose the right type of cache based on the requirements of the web application.