PNP or NPN transistor

PNP or NPN transistor, sometimes it is not that obvious. This little summary hopefully helps someone who still confused when and how to use them.

I would like to give you some ideas how I learned when and which to use.

• current always flows from Collector to Emitter
• Collector should be connected to the middle letter of the transistor [nPn or pNp]
• Base will ‘open’ when connected to the first letter of the transistor[Npn or Pnp]