A write-through cache is a type of caching mechanism used in computer systems to improve data retrieval speeds. In this method, when data is written to the cache, it is simultaneously written to the main storage. This ensures that the cache and the main storage are always synchronized, reducing the risk of data loss. The main advantage of a write-through cache is its simplicity and reliability. Since data is consistently updated in both the cache and the main storage, it minimizes the chances of inconsistencies. However, this approach can lead to slower write operations compared to other caching methods, as each write requires updating two locations.