Different sizes USB cables... USB type a.. main gadgets device's Type b mini..old gadgets android phone camera Type c ..new smartphone laptop games controller

 Different sizes USB cables... USB type a.. main gadgets device's main machine to connect for every cables has this pin USB cable corner thick called  as type a keyboard pendrive mouse mobile charger cable etc for usb a in .

Type b mini..old gadgets android phone camera MP3 player game controller in Port has less time port run after it micro USB  changes it now mini port use less and old devices use it 

Type b micro mobile phone power bank smart watch Blue tooth speaker's wireless earphone to many gadgets use it port mini usb port less than thin .

Type c ..new smartphone laptop games  controller use in it both side connector use data transfer speed before port than fast battery Faster charger .

OTG cable on the go charger same as charger cable but cable is small by use this keyboard.mouse and other device mobile with connect it.