Aniroodh Sivaraman, 

The Hindi/Sanskrit word sadhu, what does it mean?

Are all the persons shown in the procession of men above sadhus?

Who is a sadhu?

One way to look at this is if one sees a photo of a procession of people in China, what question would it be?

Are all those persons Chinese?

Then what does chinese mean?

People with black hair, pajama pants and wooden shoes?

And are all such people computer engineers?