There have been many pioneering technologies, but we think these are the most influential.
It has been a long road for cars to reach this point, whether your key interest in a car is performance, safety, reliability, utility, style, or comfort. For example, we've gone from wooden 'artillery wheels' wheels in the early 1900s to carbon fiber wheels here in the 2020s. Cars used to be built to be as solid as possible and with safety being touted as a benefit, but now we have crumple zones to absorb impacts and airbags to absorb possible human impact inside the cabin. Some innovations' benefits have crossed categories, like disc brakes for both performance and safety, and turbocharging for performance and fuel economy.
What follows here is not by any means an exhaustive list of innovations since the first car was made. But it is what we consider to be the most interesting and impactful in creating the modern car.
You can still find drum brakes on the cheapest of cars. Essentially, drum brakes consist of a cylinder that the brake pads that are pressed outwardly onto the inside of a cylinder, known as the drum. Disc brakes use a disc and the brake pads clamp onto from either side. The pressure exerted is smoother and more proportional, making the brakes easier to apply smoothly. They also last longer, particularly under heavy use, recover faster after getting wet, and don't overheat as easily. The first example of disc brakes appeared in the UK as far back as 1890 but were impractical as Frederick William Lanchester used copper discs. They were then developed on motorcycles but found long-term use on trains in the 1930s.
On cars, they were a novelty for some time. Chrysler had a non-caliper-type disc on some models in 1950, but it was in racing that disc brakes made their first real impact. Jaguar used Dunlop disc brakes at the 1953 24 Hours of Le Mans. The C-Type was the first car to average over 100 mph and was reliable under braking when others weren't. The first mainstream car to feature the tech was the original Citroen DS.
Citroen, Saab, and DKW all figured out that front-wheel drive was a useful configuration. Germany's DKW first used the format in 1931, but it was Sir Alexander Arnold Constantine Issigonis who changed the automotive world when he designed the Austin Mini. He worked out that if the engine could be mounted transversely, as in across the width of the engine bay rather than from front to back, it would be a much more compact arrangement. That compact arrangement means that the cabin of a small car could be longer without changing the overall footprint. It's a design that changed the automotive landscape and is still used today in everything from compact cars to large SUVs, with a range of engine configurations having been used over the decades. Among the many benefits, FF vehicles have good front end grip on snow due to the engine's weight being over the driven wheels, and with no rear driveshaft, the transmission tunnel doesn't impede rear floor space.
Forced induction dates back to Gottlieb Daimler in 1855, but a Swiss engineer created the first turbocharger that went on to become commercially viable. By forcing extra air into aircraft engines, it offsets the effect of decreased density of air being mixed with fuel at high altitudes. The technology then moved into ships and then diesel-powered trucks. In the 1950s, American companies blazed the first production turbocharging trail with the, albeit short-lived, Corvair Monza and the Oldsmobile Jetfire. The problem was turbo lag.
The BMW 2002 Turbo was the first truly popular turbocharged car, but it had reliability issues. Porsche then used the technology to create the Porsche 911 Turbo, the fastest road car you could buy in 1974, that the idea of turbocharging desirable. Maserati decided that if one turbo was a good thing, two would be even better and gave us the Biturbo in 1981. That was supposed to reduce lag, but Porsche went further and used sequential turbos in the 959. Now we have incredibly sophisticated twin-scroll turbos that make lag unnoticeable and they are used for both performance and fuel economy.
Once upon a time, we had to use directions given or physical maps to navigate in a car. That all changed when Mazda used the US military's Global Positioning System (GPS) in the Japan-only Eunos Cosmo in 1990. Before that, automakers came up with novel ways to use physical maps. The direct precursor to GPS navigation was Toyota's CD-ROM navigation system that stored maps in its memory and showed them on a screen using a color display. Aftermarket navigation became a large industry serving those that couldn't afford factory options or moved from car to car. Now almost everyone has a GPS system on their phone in their pocket, which has led to automakers supporting that function in infotainment systems with Android Auto and Apple CarPlay while continuing to provide options for inbuilt navigation services.
While the tech may have had its fair share of issues, now, you're unlikely to ever get lost.
It's hard to understand the pushback there was at the time when seatbelts were made mandatory to wear on public roads by law. However, studies in the mid-1980s showed that seat belts reduced injury and death in car accidents dramatically. More recently, the combination of seatbelts and airbags is understood to have reduced fatalities by half. We have to go back to the mid-19th century to find the first seatbelt, though. It was invented by the English engineer George Cayley for his glider, but it wasn't until 1946 that a Californian doctor came up with the idea of a retractable seatbelt. The now-defunct car maker Nash put them in their cars in 1949, but enough customers demonstrated they didn't want them by asking the dealers to remove them that Nash declared them a sales failure. Ford then offered them as an option in 1955, but only two percent of buyers chose to have them installed.
The first three-point seatbelt, a non-retractable Y-type design was designed by Roger W. Griswold and Hugh DeHaven in 1955. However, it was Saab that successfully made seatbelts as a standard feature commonplace with the introduction of the GT 750 in 1958. Then, Swedish inventor Nils Bohlin then developed the modern, retractable three-point seatbelt for Volvo as we know it today. The design was so revolutionary and Volvo was so committed to safety that the automaker gave the design away for free use across the industry.
It was the state of Victoria, Australia, that created the first law requiring seatbelts to be worn in 1970. The US followed through the 1980s, but laws were fought through the courts, delaying them from going into practice. Now, most people don't think twice as it's a habit to put one on and buckle-to-drive technology is quickly becoming a standard that will prevent you from driving without wearing one.
Since the dawn of the car, engineers have understood that the greatest resistance to cars is air. Land speed racers in the 1800s built cars that looked like they were influenced by boats, and in 1914, Alfa Romeo designed the first known streamlined vehicle, but the extra weight of the bodywork didn't improve the base car's speed. The German Rumpler "Tropfenwagen" (teardrop car) from 1921 was more successful, and its Coefficient of drag (Cd) of .28 stands up today as being slippery through the air. The "streamliner" design became mainstream, as seen in examples like the Chrysler Airflow from 1934. It wasn't until the late 1950s that there was a renewed interest in aerodynamics, and that took place in the racing world. Not only did slippery cars go faster, but British researcher G.E. Lind-Walker started a revolution in motor racing by demonstrating the role downforce could have in acceleration, braking, and cornering. Wings and spoilers started to appear on road cars, and the relationship between race cars and road cars in aerodynamics and styling started.
In 1980, Ford introduced its keyless system that used a number code entered into a five-button keypad mounted on the driver's door to unlock. However, it was Renault in France that introduced the first remote keyless system in 1982 with the Fuego. Then, General Motors brought it to the masses in the early 1990s. Now we don't even need to take the key fob out of our pockets to open many modern car doors. Instead, a transponder senses when the fob is near and automatically unlocks and can then lock the car again when the transmitter leaves the area. While that seems like a recent invention, the first "passive entry system" was available on the 1993 Chevrolet Corvette.
The technology has loads of life in it still, and while Tesla has used key cards, it seems the next big thing will be phone-as-key technology.
The first automatic transmission was called the "horseless carriage gearbox" and appeared in 1904, but General Motors introduced the first mass-produced automatic transmission in 1939. While automatic transmissions make life easier on the driver, they aren't known for changing gears particularly fast. For that, you want a dual-clutch transmission (DCT) with one clutch handling the even-numbered gears while the other handles the rest.
The idea of a DCT stretches back to a French military engineer before World War II, but he never brought the concept to life. The first production car with a DCT was the British Hillman Minx in 1961, although that was more semi-automatic than fully automatic. Racing took up the mantle when Porsche started using the concept in its 962 C car in 1985. It wasn't until 2003, though, that the first modern road car with a DCT appeared. The Volkswagen Golf R32 was the first car, using a dual-clutch to fire off gears rapidly and keep the engine on the boil.
Electronic Stability Control (ESC) has likely saved more lives than any other automotive innovation. Every new vehicle in the US is mandated by law to have an ESC system. The basic premise is a computer sensing understeer (front wheels slipping) or oversteer (rear wheels slipping) automatically applies brakes or throttle to counteract the problem and allow the driver to retain control of the vehicle. Technically, the Toyota Crown in 1983 was the first car to come with an "Anti-Skid Control" system, but BMW was improving upon its traction control system with Bosch in the early 1990s and applied it to its entire model line in 1992. Mercedes, also working with Bosch, brought its ESC system into production in 1995 with its S-Class Coupe at the same time as Toyota's Vehicle Stability Control System appeared in the Toyota Crown Majesta.
It took time for the technology to become relatively inexpensive, but heading into the 2000s, most automakers either offered it as an option or as standard. In 2012 it became mandatory in production cars sold in the US. According to the NHTSA studies, ESC alone has decreased fatal single-vehicle crashes of SUVs by 56 percent.