I am making my own arduino. I am in the process of hooking up power to the Atmega328.
In both these articles they use the L7805 voltage regulator with two 10uF capacitors.
https://www.arduino.cc/en/Main/Standalone
http://www.instructables.com/id/How-to-Build-an-Arduino-Uno-on-a-BreadBoard/?ALLSTEPS
I am looking at the datasheet for the regulator at http://pdf.datasheetcatalog.com/datasheet_pdf/sgs-thomson-microelectronics/L7805CD2T_to_L7885CV.pdf
The data sheet provides a number of figures for how to correctly hook up the L7805 in different situations (pages 4, 16-23). I think Figure 13 represents our situation (Fixed Output Regulator). In the figure they use 0.33uF and 0.1uF capacitors. Could someone explain why the examples use 10uF and the data sheet specifies 0.33uF and 0.1uF?