By Henrik Norbeck

The Swedish word for tune is lat, plural latar. The most common type of tune in Swedish music is the polska, plural polskor. It is a dance tune played in 3/4 time, though not the same way as a waltz. Other common dances are waltzes (vals, valser), polkas (polka, polkor), schottishes (schottis, schottisar), and mazurkas (mazurka, mazurkor). Other common tune types are ganglat (walking or marching tune), brudmarsch (wedding marches), and skanklat ("I want to get paid"-tunes).
There are a couple different types of polska in Sweden (and in Norway and Finland as well). Most of them are played in some kind of 3/4 time. So what makes a polska different from a waltz? Well, first of all they are ususally played at a slower pace (fewer beats per minute). But the main difference is where (and how) you put the stress. A waltz has three beats per measure. The first one is heavy and has a "downward" feeling, and the other two are light and have an "upward" feeling, so your typical waltz goes something like "bom - bip - bip", or you could write it graphically as:
\ ' ' \ ' ' \ ' '
In a polska, on the other hand, beats 1 and 3 are heavy and downward, and beat 2 is light and upward, something like "bom - bip - bom":
\ ' \ \ ' \ \ ' \
The player usually taps his foot on beats 1 and 3. In some parts of western Sweden polskas are called springlek. In Norway they are also sometimes called springar or pols. The different types of polska are:

Even polska (jamn polska)
The beats can be divided into two eighth notes of equal length. The beats are often divided into sixteenth notes. This type is common in the southern and eastern parts of Sweden, and in Finland.

It is a bit like a polka with three beats per bar instead if two. It is also sometimes called sl?ngpolska or sextondelspolska. In some parts of eastern Sweden and Finland, people play even polskas with all beats of equal stress. In many of these polskas it is still possible to group the beats into multiples of three, but there are many tunes where this is not possible. This polska, for example, has one bar with four beats.

Uneven polska (ojamn polska)
The beats can be divided into three triplets, or two notes of unequal length. In some parts these polskas have so many triplets that they are called "triplet polska" (triolpolska), but the most common version has more two-note figures than triplets. This kind of polska is usually written with straight eighth notes or dotted eighth + sixteenth. The rhythm has more of a triplet feel, however.

This is a bit like an Irish slip jig or hop jig. It is sometimes called attondelspolska. This kind of polska is played over most of Sweden and Norway.

Polska with short first beat (polska med kort etta)
This is where the rhythms start getting complicated. This is a relative of the uneven polska, but the first beat is shortened and the second one is prolonged. The rhythm is a bit like 2+4+3/8 time. This type is common in the west of Sweden and in parts of Norway.

Polskas like this one would usually be written as if the beats were of equal length. Writing it with triplets as I have written it here, is not entirely true, since there are no even three beats per bar to refer to. There are only three beats of different lengths (short, long, medium). I'll rewrite this example in 2+4+3/8 time, when I find the time.

Polska with long first beat (polska med lang etta)
This rhythm is even harder to understand. The first beat is prolonged, and the third one is shortened. A bit like 4+3+2/8. Usually the player taps his foot on all three beats. This type is also common in the west of Sweden and in parts of Norway.