noImplicitAny

When there are no type annotations for a variable, TypeScript will assume the type as any. This can cause a wide variety of errors to be missed by the compiler.

If strict or noImplicitAny is set to true, an untyped value will produce a compiler error.

This flag does affect certain cases of dynamic let assignment.

The noImplicitAny flag will prevent you from using dynamic types without an explicit declaration.