What is the role of HTTP caching and conditional requests in backend application performance?
HTTP caching and conditional requests play a crucial role in improving the performance of backend applications. Caching allows the storage of previously fetched resources, reducing the need for repeated requests and saving bandwidth. Conditional requests utilize caching by sending a request to the server with a conditional header, such as If-Modified-Since or If-None-Match, to validate whether the cached resource is still valid. If the resource is still valid, the server responds with a status code of 304 Not Modified, reducing network traffic. If the resource is outdated, the server returns the updated resource. This mechanism saves both network resources and server processing time.