Fault Tolerance
Fault tolerance is a system design principle that enables a system to continue operating properly in the event of the failure of some of its components. It involves techniques like redundancy, replication, and error handling to ensure high availability and reliability, preventing single points of failure from causing system-wide outages.
Developers should learn fault tolerance when building mission-critical systems such as financial services, healthcare applications, or cloud infrastructure where downtime can lead to significant losses or safety risks. It is essential for distributed systems, microservices architectures, and any application requiring 99.9%+ uptime, as it helps maintain service continuity despite hardware failures, network issues, or software bugs.