Update README.

README.md

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 # kbo
 Spectral Burrows-Wheeler transform accelerated local alignment search.
 
+kbo is an approximate local aligner based on converting [_k_-bounded matching
+statistics](https://www.biorxiv.org/content/10.1101/2024.02.19.580943v1)
+into a character representation of the underlying alignment sequence.
+
+Documentation is available at [https://docs.rs/kbo](https://docs.rs/kbo).
+
+## Installation
+kbo is distributed as three separate Rust packages:
+- [kbo](https://github.com/tmaklin/kbo) contains a Rust library implementing the core algorithm (this repository).
+- [kbo-cli](https://github.com/tmaklin/kbo-cli) provides a command-line interface for `kbo find` and `kbo map`.
+- [kbo-gui](https://github.com/tmaklin/kbo-cli) provides a WebAssembly graphical user interface for running kbo in the browser.
+
+## About
+kbo supports two main operations:
+
+- `kbo find` matches the _k_-mers in a query sequence with the
+  reference and reports the local alignment segments found within the
+  reference. Find is useful for problems that can be solved with
+  [blast](https://blast.ncbi.nlm.nih.gov/Blast.cgi).
+- `kbo map` maps the query sequence against a reference
+  sequence, and reports the nucleotide sequence of the alignment relative to
+  the reference. Map solves the same problem as
+  [snippy](https://github.com/tseemann/snippy) and [ska
+  map](https://docs.rs/ska/latest/ska/#ska-map).
+
+kbo uses the [Spectral Burrows-Wheeler
+Transform](https://docs.rs/sbwt/latest/sbwt/) data structure that allows
+efficient _k_-mer matching between a target and a query sequence and
+fast retrieval of the _k_-bounded matching statistic for each _k_-mer match.
+
 ## License
 kbo is dual-licensed under the [MIT](LICENSE-MIT) and [Apache 2.0](LICENSE-APACHE) licenses.