> For the complete documentation index, see [llms.txt](https://docs.fluentbit.io/manual/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fluentbit.io/manual/2.1/readme.md).
# Fluent Bit v2.1 Documentation
[Fluent Bit](http://fluentbit.io) is a Fast and Lightweight **Telemetry Agent** for Logs, Metrics, and Traces for Linux, macOS, Windows, and BSD family operating systems. It has been made with a strong focus on performance to allow the collection and processing of telemetry data from different sources without complexity.
## Features
* High Performance: High throughput with low resources consumption
* Data Parsing
* Convert your unstructured messages using our parsers: [JSON](/manual/2.1/pipeline/parsers/json.md), [Regex](/manual/2.1/pipeline/parsers/regular-expression.md), [LTSV](/manual/2.1/pipeline/parsers/ltsv.md) and [Logfmt](/manual/2.1/pipeline/parsers/logfmt.md)
* Metrics Support: Prometheus and OpenTelemetry compatible
* Reliability and Data Integrity
* [Backpressure](/manual/2.1/administration/backpressure.md) Handling
* [Data Buffering](/manual/2.1/administration/buffering-and-storage.md) in memory and file system
* Networking
* Security: built-in TLS/SSL support
* Asynchronous I/O
* Pluggable Architecture and [Extensibility](/manual/2.1/development/library_api.md): Inputs, Filters and Outputs
* More than 100 built-in plugins are available
* Extensibility
* Write any input, filter or output plugin in C language
* WASM: [WASM Filter Plugins](/manual/2.1/development/wasm-filter-plugins.md) or [WASM Input Plugins](/manual/2.1/development/wasm-input-plugins.md)
* Bonus: write [Filters in Lua](/manual/2.1/pipeline/filters/lua.md) or [Output plugins in Golang](/manual/2.1/development/golang-output-plugins.md)
* [Monitoring](/manual/2.1/administration/monitoring.md): expose internal metrics over HTTP in JSON and [Prometheus](https://prometheus.io/) format
* [Stream Processing](/manual/2.1/stream-processing/introduction.md): Perform data selection and transformation using simple SQL queries
* Create new streams of data using query results
* Aggregation Windows
* Data analysis and prediction: Timeseries forecasting
* Portable: runs on Linux, macOS, Windows and BSD systems
## Fluent Bit, Fluentd and CNCF
[Fluent Bit](http://fluentbit.io) is a [CNCF](https://cncf.io) **graduated** sub-project under the umbrella of [Fluentd](http://fluentd.org). Fluent Bit is licensed under the terms of the [Apache License v2.0](http://www.apache.org/licenses/LICENSE-2.0).
Fluent Bit was originally created by [Eduardo Silva](https://www.linkedin.com/in/edsiper/). As a CNCF-hosted project, it is a fully **vendor-neutral** and community-driven project.
---
# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.
## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:
```
GET https://docs.fluentbit.io/manual/2.1/readme.md?ask=&goal=
```
`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.