Thank you, I do appreciate this. But I have a class assignment, and I have to show the LEDs in the arduino (as my instructor had shown me in class) This might not be the best thing to do, but it's a one off and I don't have access to a breadboard and resistors! I'd be very grateful for any help!
He may also learn something.
I have used LEDs without resistors on the Arduino by using PWM. If you have the duty cycle short enough, the light isn't that bright, and I believe most LEDs can handle the short burst of current. Plus, the Arduino pins don't put out that much current.I think it's harder than people think to damage the pins. I've accidentally shorted out a pin and had it output 5 volts. It was fine You can use pins 3,5,6,9,10, or 11Use analogWrite(3,5) to turn on the LED in pin 3Use analogWrite(3,0) to turn it off.You can change the second number to make the LED brighter or dimmer.BTW, you can get clone Arduino nanos for $2 or so, so it's not the end of the world if you try something out like hooking up an LED without a resistor.You learn by doing - even doing dumb things.