Angular Velocity and Angular Frequency

Homework Statement

Hi all, I am a bit confused about angular frequency, specifically in the case of a pendulum (bob pendulum or physical pendulum). Also, what's the difference between angular frequency and angular velocity?

Homework Equations

I understand that a physical pendulum is governed by the relation theta = thetamax Cos (omega*t + phi), where omega = (kappa/I)1/2, where -kappa*theta = torque. But also if I take a derivative with respect to time, I get d theta/dt = - omega*thetamax*Sin(omega t + phi). Isn't this d theta/dt also omega? But, say, when d theta/dt is maximal, d theta / dt = omega' = omega * thetamax

The Attempt at a Solution

My question is, what is the difference between these two omegas? Is it even appropriate for me to call d theta / dt, omega? Additionally, the tangental speed a distance r from the center of mass is v = r*omega. But should I be using omega or d theta/dt? My textbook doesn't explain this to me. Thanks for giving this a look over.