Gamma testable questions

Guys, I dont have time to read notes and Gamma for me is like a blue sky.

So could you tell me key bullet notes which are commonly testable and I must know?

Like when it is negative, when positive, etc.

Gamma’s always positive (for long positions).

It’s close to zero for far in-the-money and far out-of-the-money options.

It’s highest near the strike price, and gets higher the closer you are to expiry.

Can’t make it much simpler than that.

Gamma is negative for short call/put.

Also know that Gamma is a second-order variable, while delta is a first-order variable.

Good point. I amended my post, above.

Gamma measures the sensitivity of Delta to price changes of the underlying