The introduction of retryable writes in MongoDB enables clients to send writes safely, without relying on the server's acknowledgment, reducing error handling complexity and improving reliability. This feature allows drivers to implement retry logic at the client level, using a connection setting of `retryWrites`, which is particularly useful for transient network errors or primary elections. On the server-side, retryable writes are implemented by checking against the transaction table, which contains logical sessions IDs, last seen transaction IDs, and pointers into the oplog where operations were recorded. This approach ensures that only one attempt to retry a write occurs, making it suitable for applications with transient network issues. The integration of retryable writes with transactions provides a foundation for eliminating transient network faults or primary elections from preventing transactions from being committed.