People sometimes think that that Chasidic means simply "extremely religious," or refers to Jews with a lot of black in their wardrobes.
In the "Blues Brothers," when Aretha Franklin says to her husband, "There are two honkies out there dressed like Chasidic diamond merchants," she's referring to their suits and hats, not to their spiritual personalities.
Being Chasidic is about much more than simply appearances. Chasidism is a Jewish revival movement which was started by Israel Ba'al Shem Tov in the 18th century.
It particularly insisted on inward devotion, and not just external observance. Chasidism taught that the sincere service of a simple person can be worth as much as that of a scholar.
It believed that every-day acts could be done with holiness and awareness of God. One of the disciples of the Maggid of Mezerich said, "I went to the Maggid in order to see how he ties his shoelaces."
Chasidism placed much emphasis on worshipping with joy. Chasidim sang and danced a great deal, and in many places still do.
The Chasidic rebbes taught acceptance and love for all Jews. The Rebbe of Karlin famously said: "I love the wicked man who knows that he is wicked more than the righteous man who knows that he is righteous."