# About

The important types of query are:

* **Alert queries**: queries that highlight issues in specific locations in your code
* **Path queries**: queries that describe the flow of information between a source and a sink in your code

You can add custom queries to [CodeQL packs](https://codeql.github.com/docs/codeql-cli/about-codeql-packs/) to analyze your projects with “[Code scanning](https://docs.github.com/en/code-security/secure-coding/automatically-scanning-your-code-for-vulnerabilities-and-errors/about-code-scanning)”, use them to analyze a database with the “[CodeQL CLI](https://codeql.github.com/docs/codeql-cli/#codeql-cli),” or you can contribute to the standard CodeQL queries in our [open source repository on GitHub](https://github.com/github/codeql).