When to use and not to use Mockito Argument Matchers. difference between any(), anyString(), Mockito.anyString(), Mockito.any()?

Question

Hi I am very new to mockito framework. Can you please explain in lay man term why we need argument matchers and what is the need of any(), anyString() and what if I use a correct string instead of anyString() will it logically correct? And why these methods are static?

import static  org.mockito.ArgumentMatchers.anyString; 
import static  org.mockito.ArgumentMatchers.any;

resourceLoader.getResource(anyString())// returns a input stream 
ObjectMapper.readValue(Mockito.any(), Mockito.any())  // takes a input stream and an object

Also what is the difference in using directly and Mockito.anyString() and directly anyString()?