User Input not working with keyboard.nextLine() and String (Java)

For you code Change nextLine(); to next(); and it will work.

System.out.println("Was that in Celsius or Fahrenheit?");
    System.out.print("(Enter 'C' for Celsius and 'F' for Fahrenheit) ");
    type = keyboard.next();

to get an idea for you to what happened was this:

• nextLine(): Advances this scanner past the current line and returns the input that was skipped.
• next(): Finds and returns the next complete token from this scanner.

Also like the many of the answers says use equals() instead of using ==

The == checks only the references to the object are equal. .equal() compares string.

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