Why do moving charges produce magnetic field ? What is the logic behind magnetic field produced in current carrying conductors ?

Why do moving charges produce magnetic field ? What is the logic behind magnetic field produced in current carrying conductors ?

Moving charging cause a magnetic field - well, just because! Actually magnetic fileds and electric fields are closely related, and in special relativity are not considered to be fundamentally different (the perecption of electrical and magnetic fields depends on the observer's frame of reference). But for a basic undersanding of electricity and magnetism you can consider the phenomenon of moving charged particles causing a magnetic field as a fundamental rule of nature - sort of like Newton's Laws.