Prompt caching is an optimization technique used in large language model (LLM) applications to enhance efficiency by storing and reusing responses to identical prompts, thus reducing latency and operational costs. This approach is particularly beneficial for applications using extensive prompts, as it minimizes the computational resources required by avoiding repetitive processing. Model providers like OpenAI and Anthropic have implemented distinct methods of prompt caching, each with its own cost implications and operational parameters. OpenAI's approach offers significant latency reduction and cost savings by caching static content and using automatic cache management, while Anthropic allows for more user control over caching sections with specific pricing structures. The benefits of prompt caching extend beyond cost-efficiency, contributing to scalability, improved user experiences, energy efficiency, and enhanced security by decreasing the frequency of sensitive data processing. However, challenges such as cache management, resource constraints, implementation complexity, and security risks need careful handling to maximize the potential of prompt caching without compromising system performance.