Electrical help required in DIY LED circuit

[lifesci]

Hi Christie,
Thank you for the informative reply. I, now, understand the voltage part, but am still confused about the current. I will be using series instead of parallel. My question now is whether the current is also split along the length of the circuit after passing each LED? Like you said to employ enough driver voltage to match the aggregate of all the LED's +10%, does it work the same way for current? If driver output is 1 amp, must the 5 LED's be rated at 1 amp each or 0.2amp each? I guess I'm asking if current remains constant throughout the whole circuit, unlike voltage which is lost at each LED? Must I add the current requirements of all the LED's to arrive at the 1 amp provided by the driver?