What The Heck is "Qualify"

Racing Terminology 101

This is a guide or actually an "in general" for racing & terminology. It can be called different things and so with that being said lets get to the basics.

Downforce

Starting with physics huh.
Downforce is as the name suggest, the amount of force is pushing the car to the ground. This is important as to turn a corner faster you need more grip and thus more downforce (or you under/oversteer). This can be done by using Aero parts which comes mostly in wings / spoilers.

Under and Oversteer

both of these involves either the front or rear wheels losing grip.
Understeer involves the front losing grip mostly due to faster corner entry, thus resulting in the car turning less than desire.
Oversteer you step on the acceleration too early while cornering. This means that the grip the rears give are lost due to the wheels spinning more for acceleration. Causing you to "spin out".

Qualifying

Qualifying is in essence a time trial to determine the starting lineup for a race. With drivers setting their fastest laps to determine the place order. As there are multiple ways for qualifying to go I'm covering the ways for the top in both stock cars and open-wheel (get to that later) F1 and NASCAR.
In F1 there are a permanent 22 cars on race day. 3 rounds of qualifying (Q1-3) with Q1 & 2 knocking the 6 slowest drivers. Then in Q3 is the deciding time trial for the top ten.
NASCAR is different, there is a list of cars that attempt to qualify, and some of them simply, don't.
With tight packed, Oval racing prevalent, it is common for someone to F#ck things up for the grid and end Quali in a wreckfest. So NASCAR goes at it by letting drivers go out for 1-2 laps depending on the type of track, taking the best result and that's the starting order.

Pole

This goes along with qualifying pretty hand & hand. Pole is simply the driver who sets the fastest lap and thus is the 1st on the starting grid.

DN- what now?

When something starts with the term "DN" it simply means did not. As an example these are the most common "DN's"

DNF = "Did Not Finish"

DNQ = "Did Not Qualify"

DNS = "Did Not Start"

Pit, like Brad Pitt?

Pit, a car cannot go a full race without a change of tires or refueling (F1 doesn't allow refueling). So they make a "Pit stop" where they change tires and refuel. They do this in the "Pitlane an area Off the main track so they don't get rear ended when stopped.

Below is the Pitlane for Spa-Francorchamps Highlighted

Out, Prep, and hotlaps

Outlap is simply when the car first gets out of the Pits, the tires are very cold and with that has little to no grip. And thus a driver should try there best to warm them up by weaving and hard braking on straights.
The Prep Lap is the lap after an outlap where similarly you are trying to warm up your tires and along side brakes.
Hot laps are timed laps where it is those laps that are used to determine starting line up in qualifying.

Flags

communicating to a driver going 200mph is a handful, thus the flags. The three common flags are
Green Flag = "good to go" race as normal
Yellow Flag / Caution = "Slow down", debris or a bad driver is causing a hazard
Red Flag = "Stop the Race go back to Pits", major crash or extremely bad weather.
Chequered Flag = "Race done" flown at the end of a race, it signals that the race's done mate.

Open Wheel

simple the wheel is outside the main chassis. Most notable are F1 or IndyCars.

Closed Wheel

The wheels are under something and thus "closed". Examples are NASCAR or GT3.

Conclusion.

This is not all. I can tell you that when talking about and especially corners / turns, it is a handful to get through. And so that is all for now, hope you learned something new. If you have questions ask in the comments and it MIGHT get covered by.