unknown.ts

// Anything is assignable to unknown
const foo: unknown = 1 // <- we can assign a number to a unknown var
const bar: unknown = true // <- same with other primitive types such as boolean

// But unknown isn’t assignable to anything but itself
const myString: string = foo // <- ⛔️⛔️⛔️ unknown type is not assignable to string type
const isGreaterThan10 = (val: unknown) => val > 10 // <- ⛔️⛔️⛔️ because val has unknown type