system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: How do plasma globes work?
gpt
The ball is filled with an inert gas at a low pressure (argon, neon, nitrogen).

The socket houses a special transformer that creates a high voltage at high frequency (but low current). That means the ball in the middle is constantly charged and discharged between + and - of a few kilovolts.

This causes an alternating electrical field to build between glass orb and metal center. This is strong enough to rip electrons of the gas atoms (low pressure means less gas, and each individual atom is exposed to more of the field)

Free electrons or gas atoms missing one have a net charge and are therefore accelerated very quickly in the field causing a cascade of more ionizations by hitting other atoms and ripping their electrons away.

This causes individual channels of ionized (glowing) gas to form.

These channels (filaments) stay together because of an instability, heat up, and slowly move upwards.

You can direct them by placing your hands on the glass because that locally grounds the glass  wich lets excess charge flow away through you, and more channels can form there.