How do straws work?

They work very hard.

No.

Straws work because of air pressure.

Is it similar to acupressure?

No.

Air pressure is the weight of air pressing down on earth and all other objects present on it.

Now, when a straw is in a liquid, the air pressure upon the liquid in the glass.

The air pressure upon the liquid in the straw is similar.

Causing the levels of liquid to be almost equal.

However, when we drink the liquid through straw.

We first inhale causing the air from the straw to flow into our lungs.

Now due to absence of air, the air pressure in the straw decreases.

Hence, the air pressure present on the liquid of the glass pushes the liquid into the straw

Causing it to move upwards and thus, helping us drink.