cross

Crosses are regular, pointed figures, commonly formed by (often perpendicular) skew lines. They are often used as symbols and signs.

A curve composed of equal line pieces through the origin is called a line star.
The figure can be oblique (as the character x or the multiplying sign x) or perpendicular (as the summation sign +).

In the Netherlands a number of public health organizations have a cross in their emblem: the Red Cross, the Green Cross and the Ivory Cross (and the former organizations: Orange-Green Cross and White-Yellow Cross).
The cross is used as military decoration, and it has religious meaning as the crucifixion of Jesus Christ. And the cross is used as symbol for the death.

The right-handed swastika is on old symbol used in various cultures to denote prosperity and good fortune ¹⁾.
Adolf Hitler adopted the left-handed swastika for his National Socialism.

There is also a quartic swastika curve.

Double skew lines are used in music notation as the sharp: #.

The 'cross of Einstein' is a fourfold image of an celestial object, where gravitational fields act as a lens.

notes

1) The word swastika has been derived from the Sanscrit.