I'm old but I'm discovered new every day Reinvented over time with new nuance, My evolutions are reviled by some and loved by many. I have the power to possess those within earshot, causing shaking and flailing of limbs, or sometimes just the tapping of tips.

I’m known for how I bend, and how I protect. Against the former I fend, and the latter, deflect. At times I’m used as slang for myself, while referencing how good I am for your health. I’ve many more uses, but one last good clue: If you’re me, your opponent is glue.

I exist so meetings that should have been emails can happen.

We are -fill in the blank-! You love us, and you, well, not so much love us But in the end, we always got your back.

What do you use to stop someone from advancing?