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Power up is you staking your liquid tokens so that you can share rewards to other users when you upvote them.

Powerdown is the reverse, I think.

I'm learning here too.

Sir @taskmaster4450le would answer better.

Powering up gives you increased voting power which makes your vote worth more. It also allows for more engagement on the networks.

Yes powering down is the reverse....lowers the vote amount and give you less ability to interact.

power up means stake while down means unstake