Shopping for Arduino

Hi, Im on a buisness trip in Egypt and I found that electrical components are very cheap here. So I already got me some cool parts. However I am just a beginner so I dont know what other cool parts are out there. Here is a list of parts I already got:

Shift regsiters 7 segment LED EEPROM DIP Shwitches LEDS servos dc motors

I think a H bridge is cool too, but I dont know wich is good and safe to use (I have read something about kickback diodes) So please tell me what cool parts I can also get so I can expand my knowladge cheaply :)

If you're using any sort of inductor (motors, relays, solenoids, etc), you'll want a protection diode when using them with ICs, transistors, etc. The brief high voltage produced when the inductor is switched off can fry the semiconductor.

This is more on transistors, but for safety's sake, some information could apply to microcontrollers:

Resistors, capacitors, potentiometers, transistors, and push buttons are always great to have in your electronics toolbox. Beyond some of the basics, it's really based on what your project or interests are. Have fun!

Oh, also on the note of transistors, there are multiple kinds. Bipolar junction transistors are the ones you probably see the most. These are either NPN or PNP. These are generally used where current amplification is needed. FETs are transistors such as JFETs, MOSFETs, etc. Those would be used where voltage amplification is needed.

These are great electrical components to learn about and how to use them. Especially if you're interested in robotics or inductor switching projects (e.g. using relays for switching lights).