Even those who take little more than a passing interest will know there have been several champions of both F1 and IndyCar. We are talking about Mario Andretti, Emerson Fittipaldi, Nigel Mansell and Jacques Villeneuve.
But how easy or difficult was it for that illustrious quartet to switch from one category to the other? And also, in more recent times, for other well-known names such as Juan Pablo Montoya, Romain Grosjean and this year's Indy 500 winner Marcus Ericsson?
Planet Sport runs down the key similarities and differences.
There is a reason why we are starting here because, at least to some if not most of us, when comparing and contrasting F1 and IndyCar the first thing that springs to mind is geography.
Formula 1 is, of course, a global series. It is a World Championship and features races in Europe, North America, South America, the Middle East, Asia and Australia, and will return to Africa in the next couple of years.
However, IndyCar is currently staged exclusively in the United States.
It has not always been that way - in the past, races were held in England (at the now defunct Rockingham Speedway in 2001 and 2002 and Brands Hatch the following year), Germany, Belgium, Netherlands, Japan, Canada, Brazil, Mexico and Australia.
Several of those were very short-lived or even one-offs though, and the 17-race 2022 campaign is taking place at 14 different venues in the US.
Naturally we gravitate towards circuits next because again, there is a fundamental difference in the mind's eye when thinking about IndyCar juxtaposed with F1.
That is the presence in IndyCar of oval circuits, where the cars lap anti-clockwise with braking only necessary to avoid an accident or when entering the pit lane.
But in 2022, only four of the 17 races are on ovals, each at different venues, the most famous, of course, being the Indianapolis 500.
Otherwise, there is a similarity with F1 in regard to a mixture of street circuits - in places such as St Petersburg (Florida), Long Beach and Nashville - and permanent road courses, thereby offering drivers a variety of different tests.
F1's circuits that are either partially or wholly based on public roads are in Jeddah, Melbourne, Miami, Monaco, Baku, Montreal, Singapore and, from 2023, Las Vegas.
Here lies a significant difference between the two series, because F1's system of 10 different constructors, running two cars each, appears somewhat easier to understand.
Admittedly the lines are blurred slightly with Red Bull also owning AlphaTauri, but those two teams operate independently in separate countries and also have markedly different liveries.
But in IndyCar, there are 17 different teams, four of which have Andretti in the title!
For instance, ex-F1 racers Grosjean and Alexander Rossi drive for Andretti Autosport, but there are also three other drivers whose team name comes under the Andretti umbrella with outside support.
A similar situation exists at Dale Coyne Racing, who have separate branches for another former F1 driver, Takuma Sato, and David Malukas.
Talking of drivers, this takes us on to how many compete in IndyCar - this year's roster comprises a whopping 37 names.
Only 21 have raced in F1 so far and that was only because Nico Hulkenberg had to deputise for Sebastian Vettel when he had Covid-19, otherwise it would have just 20.
Not all of the 37 will contest every round and generally a field of 26 or 27 will line up on the grid for an IndyCar race - although the Indy 500 was able to accommodate 33.
Of the 37 in IndyCar this year, six have had F1 experience by way of either racing or, in the case of Callum Ilott, as a recent official reserve/free practice driver.
Colton Herta and Pato O'Ward, both of whom have connections with McLaren, are the leading candidates to make the opposite move in due course.
It has to be said IndyCar is a much more unpredictable series than F1 which, in 2022, has had Ferrari and Red Bull as the only winning teams in the opening 11 races.
That meant four different drivers, while IndyCar has had six individual winners at nine events with Josef Newgarden (three) and Scott McLaughlin (two) the multiple victors.
Only the first 10 finishers in Formula 1 score points, whereas everyone that participates in an IndyCar race receives a token five as a minimum.
It's 50 points for the winner - double the F1 tally - and then a much less steep sliding scale thereafter and only a one-point drop for each position after 10th. Double points are on offer at the prestigious Indy 500.
While F1 offers an extra point for the fastest lap of a race, and points for first to eighth places in this season's three sprint qualifying 'races', IndyCar also has a few bonus opportunities.
There is a point for pole position, one for leading a race lap and two for the most laps led in a race, while qualifying for the Indy 500 also offers points for the 'Fast Twelve' at the front of the grid.
Use of more than the permitted number of engines in F1 means grid penalties, but in IndyCar it results in 10 points being docked.
[Insert Austrian Grand Prix pic]
As mentioned earlier, F1 has 10 different teams and therefore 10 individually-designed cars using an engine supplied by either Mercedes, Ferrari, Renault or Red Bull Powertrains.
In IndyCar, each team runs either a Chevrolet or Honda engine with a Dallara chassis and universal aero package.
To the casual observer, the F1 and IndyCar models may closely resemble each other, but they have differences regarding their safety mechanisms.
Formula 1 has the Halo, a circular-shaped device which, as its name indicates, protects the driver's head and has been credited with saving the lives of both Grosjean in 2020 and Zhou Guanyu in 2022.
IndyCar, meanwhile, deploys the Aeroscreen, which was developed by Red Bull Advanced Technologies - and is reported to be able to withstand the equivalent weight of 21 IndyCars simultaneously landing on top of it.