ELI5: Explain Like I'm 5

Helical axis

Imagine you have a really long piece of spaghetti, and you twist it around a pencil. The pencil is like the central axis of the spaghetti, and the way the spaghetti twists around it is like the helical axis. It's kind of like a spiral staircase or a corkscrew.

In science, the helical axis is often used to describe the way things move or rotate. For example, imagine you have a toy top that spins around really fast. There is a line running through the center of the top, and the way the top spins around that line is the helical axis.

The helical axis can also be used to describe the way molecules move, especially in the fields of chemistry and biology. Scientists use the helical axis to study the way molecules twist and turn around each other, like a DNA double helix.

So basically, the helical axis is like a line that describes the way things twist and turn, kind of like a spiral. It's a way scientists can describe how things move in a really detailed way.