Fluent Bit is a high-performance, lightweight log, metrics, and traces processor and forwarder, part of the CNCF and Fluentd ecosystem. It supports Linux, Windows, MacOS, and BSD systems, running on x86, ARM, and other architectures. Key features include low CPU/memory usage, data parsing (JSON, Regex, LTSV, Logfmt), reliability with backpressure handling and buffering, and built-in TLS/SSL for secure networking. It offers a pluggable architecture with over 70 built-in plugins for inputs, filters, and outputs, extensible in C, Lua, and Golang. Fluent Bit also provides SQL-based stream processing for data manipulation, analytics, and timeseries forecasting. Widely adopted in production, it integrates with backends like Elasticsearch, Kafka, AWS, Azure, and more, making it a versatile solution for log and metrics processing.