Freylekhs (also called Karahod, Redl)

Video:  Dancing a Freylekhs
Video:  Learning to improvise

This is the major group dance of the Eastern European Jews. It's the one you see in all the old movies. You will also see people doing a version of it at most weddings and bar mitzvahs. The concept is simple. Either a line or circle (or both formations interchanging) formation, everyone steps in their own way to the music. This doesn't mean that it's a free for all. There are characteristic movements
like a shuffling sort of walk, a two-step, alternately stepping and stamping. The circle/line can move to the right or to the left, snaking
around the room. People can go into the middle of the circle to show off their moves. Often, the circling figure begins after completing a grand march, the details of which are described in my Syllabus.  Briefly, the grand march consists of casting off by ones, twos, fours, eights, in kind of a procession.  The thread the needle figure (below) can also be a part of this dance.

 Grand March in progress. We've casted off in twos.

 Casting off by fours

 Improvising with handkerchiefs.

I see people doing a grapevine step to this dance at most parties that I attend. However, I haven't seen that step included in any of the dance descriptions I've read. The grapevine step occurs more commonly in Israeli folk dance. Somehow, I think the wires got crossed and the step migrated from one dance style to the other. There are choreographed versions of the freylekhs in existence  (Vizonsky, Berk--liner notes from Tikva record T-117) which try to capture the overall style of the dance but are not spontaneous the way the dance was originally done. For historic descriptions see Yale Strom's reference (on reference page) as well as Miriam Shomer Zunser's description of
freylekhs as danced in 1866 (her book is on the reference page).  She mentions Heidim Deidim as  a men's figure of turning with a partner while singing "Heidim Deidim."

As an aside, here are some photos of the freylekhs from Life Magazine, 1952 .
Article by Lisa Larsen. You can view the entire issue on Google Books

The community at large probably gets confused about a hora vs. a freylekhs. The hora can mean many things. The Israeli Hora is a fast paced dance done witha shoulder hold with several characteristic steps, not really much like the freylekhs, with the basic step being the same as the Romanian sarba step. A similar dance is taught as the Chasidic Hora on the "Dancing into Marriage" video.
There is also a slow hora which is done to very slow 3/8 music, with its own distinctive footwork, again very different from the Israeli hora or the freylekhs. In Romanian dancing, the hora seems to be  a generic word for dance but quite often refers to a sort of saw-toothed patternthat moves in and out of the line of the circle. Then, if you travel through the Balkans you will find many horas, horos and oros which are really non-specific words for dance.

Threading the Needle

Threading the Needle, Ashkenaz 2004

(as demonstrated in the video "Dancing into Marriage" and in photos below)
Leader is leading the line to the left, is on the left end of the line.
I will call the leader person #1 next in line is #2 , then #3etc.
Leader #1 turns to their own right, does not pass under the arch formed between themselves and #2. Instead the leader (#1) places their own right hand (which is joined to person #2's left hand) on #1's left shoulder.

Leader then leads the line under the arch formed between person #2 & #3. #2 does not go under the arch but places their own right hand (joined to #3's left hand) on #2's left shoulder.

This process continues until everyone is wound up. While the winding is going on, people can keep time to the music by taking small steps in place.

The wound up line then snakes around the dance floor.

To unwind, the leader does their own small circle to the left, thus unwinding themselves.
Then continuing moving to the left (counterclockwise is the best way I can describe this, although you aren't in a circle) the leader leads the line under the arch between person #2  and person#3, thus allowing #2 to unwind. This continues until everyone is unwound.

An alternate method of threading/unthreading the needle,  begins with the leader passing under the arch formed between the last two people in the line, and pulling the whole line through.  As in the previous description, the leader works his/her way along the line pulling the line through subsequent arches, and winds her/himself into place at the end.  The last person who would pass under the arch each time, doesn't actually pass under and instead wraps their previously arched arm around their neck (easier to see in the video than to explain!) 

The unwinding process involves raising the arch again and pulling the tail of the line through over and over until unwound.