# Stream ciphers Sodium includes implementations of the Salsa20, XSalsa20, ChaCha20 and XChaCha20 stream ciphers. These functions are stream ciphers. They do not provide authenticated encryption. They can be used to generate pseudo-random data from a key, or as building blocks for implementing custom constructions, but they are not alternatives to `crypto_secretbox_*()`. --- # Agent Instructions: 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: ``` GET https://libsodium.gitbook.io/doc/advanced/stream_ciphers.md?ask= ``` The question should be specific, self-contained, and written in natural language. 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.