Tags are functions that receive an array of strings and then a series of arguments corresponding to values passed in the interpolation slots, allowing you to use template literal syntax while the tag function does something much more complex under the hood, potentially including returning non-string values.

You can use expressions inside template literals and those are auto-escaped for you by postgres.js

Also, template strings like sql`foobar`, graphql`foobar` and others enable syntax awareness in IDEs.

I have a big Typescript / SQL mixed codebase (No ORM), and its very nice to have VSCode syntax color and code-format TypeScript, GraphQL and SQL in the same file