Why use spyOn instead of jasmine.createSpy?

Question

What is the difference between

jasmine.createSpy(\'someMethod\')

And

spyOn(someObject, \'someMethod\')

Answer 1

Additionally to the other fine answer:

• Use spyOn() to spy (intercept) an existing method on an object to track calls of other modules to it.
• Use jasmine.createSpy() to create a function that can be passed as callback or Promise handler to track call-backs.