> For the complete documentation index, see [llms.txt](https://romebell.gitbook.io/sei-802/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://romebell.gitbook.io/sei-802/node-express/express-authentication/components.md). # Research Components We'll be breaking up into groups. Each group will be assigned a component to research and briefly present to the class. ## Bcrypt * What is bcrypt? * How does bcrypt work? * How do we use bcrypt in node? ## Sequelize Validations * What are different types of validations? * Which ones could be useful? * How do we use validations in sequelize? ## Sequelize Hooks * What is a Sequelize hook? * What are different types of Sequelize hooks? * How are hooks implemented in Sequelize? ## Sessions * What are sessions? * What is the difference between sessions and cookies? * How do we use sessions in express? ## Express Middleware * What is middleware? * What middleware have we used? * How do we create our own express middleware?