What time is it?

Using Arduino Programming Questions
1

I need to know the time of day in my sketch...
I'm on an Arduino Mega 2560.
Is there a RTC?

2

Arduino MEGA2560 doesn't have an RTC. You can get a popular RTC shield or module for arduino, based on DS1307 chip, for around $10 in lots of internet stores.

3

Example: DS1307 Real Time Clock breakout board kit : ID 264 : $7.95 : Adafruit Industries, Unique & fun DIY electronics and kits