I'm a starter of Raspberry Pi and I found that Raspberry Pi doesn’t have the usb port that could directly connect to the pc, so that I pick a Seeeduino as an Uart to Usb converter to putty up my Pi. :p
Step 1: Have a Look at the Datasheet of the Pi and Connect the Uart Port From Seeeduino (pin 0,1) to Pi
Step 2: Write a Simple Code Into Arduino.
Step 3: Open the Putty to View the Terminal of Your Pi. Remember the Set the Right Arduino Port and Speed.