service: It runs in the background on your system. For example,
- If you went to a hotel and you give your order for a soup to a server
- The server gets your order and sends to chef
- You don't know how the soup is made in the kitchen and what processes are required for making the soup
- Once your order is ready, the server brings you the soup.
background process: chef making soup
IntentService:- it's consecutive service.. (i.e) when you order many food items at a time to server but the server delivers those items one by one and not deliver them all at once.