What is Sim Racing?
A lot of people think sim racing is an umbrella term for all racing games - this is not true. Sim racing, short for simulation racing, is a niche branch of racing games, that focus on authenticity and realism, delivering a simulation game that delivers as realistic a racing experience as possible, the ultimate objective being to make the game as close to real life as possible. There are games that take this to the various degrees - some that herald themselves for being life-like simulators, with LiDAR scanned tracks to capture every bump and imperfection in the surface for that ultimate realism, along with industry-leading physics, day-and-night cycles, weather variation (rain/dry etc) and incorporating aquaplaning into their game - but when you spend your time & effort on this, you inevitably cannot provide as many cars and tracks for your game, your resources are allocated elsewhere. There are others that offer a wider range of real life cars and real life tracks, with a focus on excellent graphics, So you have a wide range of choice and really feel like you're sitting in the actual car, or driving round the actual track, but perhaps their driving physics are less life-like.
Many racing drivers choose to complement their real racing with sim racing. A decade or two ago this would perhaps seem pointless, because there was so much difference between simulation racing games and the real thing - there was little to learn, besides knowing which way round the track goes, and vague braking points etc. Nowadays, sim racing games offer very authentic models of these tracks, and of the cars, so much so that you can practice in a car on track in your racing game, sat in your rig in your bedroom, and then go to the track in real life and sit in the car, and immediately be able to transfer your knowledge picked up from the sim, which reflects in faster lap times.
I speak from personal experience that I have practised tracks like Knockhill, Silverstone and Brands Hatch on the sim, and turned up to the race day (having never visited the circuit previously), and immediately been lapping the real track at a good pace. When you consider that most circuits are usually hundreds of miles away from people (you usually have one or two that are local, but most will be far from you as they're scattered around the country), this prior knowledge gained from the sim is invaluable. Not only does it save you The fuel in going to practice days to get up to speed, You can jump in the same any time and practice as many laps as you need to. Track days and test sessions in real life are time-limited, so you might get 20 laps in a stint, whereas on the sim you can hot lap to your heart's content, for as long as you want. Furthermore, it's much nicer to practice finding a limit in your sim, and spinning out/crashing on there, where a simple click of a reset button is your refresh switch. In real life, if you bin in the car into the barrier, there is no reset switch - you just get a hefty bill and hang your head in shame, as the day is over.
So, whilst playing on Mario Kart doesn't make you a sim racer as such, that's not to say sim racers will not play games like Mario Kart, Burnout, Need for Speed etc, but their real interest is the authentic, hardcore simulation racing games.
There's never been a better time to get started on sim racing than now! There are a plethora of quality simulation games, covering various formulae like GT racing, single seater racing, drifting, rallying, touring cars etc, and there's Lots of hardware like wheels, pedals, rigs etc that Replicate the feeling of being in the cockpit of a real racing car. Furthermore, some racing is a very social experience, where are you either racing teams or with friends - Although when the red mist sets upon you, it doesn't matter whether it's your own mother in the other car, you want to win!