The talk is about Kaitai Struct, a tool for working with binary formats, especially parsing. It uses a declarative language called Kaitai Struct YAML to specify the binary formats. The speaker shares their personal experience of discovering and using Kaitai Struct, which saved them time and allowed them to work in multiple programming languages. They discuss the advantages of Kaitai Struct, including the ability to write a specification once and use it everywhere, standardization of format description, an extensive gallery of described formats, and automatic visualization of formats in a graphic diagram. The speaker also introduces a new functionality in Kaitai Struct, which is serialization, allowing the creation of binary files from an object tree. They mention the plans for future development, including support for C#, Python, and other languages, as well as the possibility of adding Wireshark disectors as a target. The talk concludes with a Q&A session where the speaker answers questions about documentation, serialization, and adding additional functionality to Kaitai Struct.