working of pulsein function.......?????

Using Arduino Programming Questions
1

hi all,
can anyone tell me about pulsein function how it work???. i read about this function but have some confusion about this.
http://arduino.cc/en/Reference/PulseIn

problem is i can't understand when we called pulsein() function so which values it read and what is the mean of pulse length which it read(Read by pulsein function).

i want make a pules counter. which count the pules from input pin.

2

pulseIn counts the length of a pulse. So if you hooked up a switch and used pulseIn on the pin, then you pressed the switch down for 283 milliseconds, that would be its return value.

Counting pulses is a completely different thing.

3

So if you hooked up a switch and used pulseIn on the pin, then you pressed the switch down for 283 milliseconds, that would be its return value.

...but expressed in microseconds.