Pspice?

How many companies have some kind of electronic simulation and what is there software called. What one should I learn?

~10^2

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for "SPICE" and for "simulat".

The concepts learned in one package readily translate between SPICE variants. LTspice from Linear Technology is a popular freeware variant.

+1 for LTSpice from Linear Technology.

you could at least try it (it's free) and decide after if you really need something more (it's enough for me, even at work).

The value to cost ratio for LT Spice is infinite!

Seriously, it is worth your time to download it and learn it.

I have compared it with products selling for hundreds of dollars and often have found it better.