OS Concepts in Layman Conditions

(If your GF doesn't already know this, she should be aware that CS colleges are the most prolific users of plugin detection software in the free world.)

Spinning lock:

To quote Lisa and Bart: "Are we still there? Are we still there? Are we still there?" - cute in small amounts, extremely irritating in large doses.

Blocking:

Examples of interlocking operations include a gate on the starting line of a horse track or a closed door in a store prior to product launch. You can't get your new iPad until some guy in a black T-shirt opens the door.

Condition:

Don't do anything (or keep doing what you do) until you hear someone else from me.