All possible subsets (power set):

All possible subsets containing up to 2 elements:

Subsets containing exactly 2 elements:

The first 5 subsets containing 3 elements:

All subsets with even length:

The 69381 subset:

All subsets of {a,b,c,d}:

The odd-numbered subsets of {a,b,c,d} in reverse order:

Use any head:

Find all ways to pick 3 elements from 4:

Draw lines between all pairs of points in an octagon:

Construct an elementary symmetric polynomial:

All possible subsets of the divisors of 10:

Find integers that have exactly 3 nonzero binary digits:

Join all possible pairs of 20 random points in 3D:

Draw lines between all pairs of points in a cube:

Subsets picks out first the elements that appear first in the input:

Different occurrences of the same element are treated as distinct:

Tuples gives all possible combinations and reorderings of elements:

Subsets[a,b,c]===Take[Subsets[a,b],c] only when all requested items are present:

When items requested by c are missing, the ones present are returned:

To suppress the warning message, use Off:

Polygons formed from all possible triples of random points: