The switch stance ollie uses a similar body motion, but the nollie is subtly distinct: For one, the rider is always moving forward, with the body positioned in a nollie stance--closer to the nose and with the front foot on the nose. Secondly the rider usually postures the body differently so as to compensate for this stance with respect to the forward motion. The rider presses the nose down using their front foot to engage the "pop" motion in order for the board to rise. This is In contrast to a "Fakie Ollie" where the pop motion is performed by the rear foot on the tail, similarly to a normal Ollie, however the rider is traveling backwards when performing a Fakie Ollie. Where in a Nollie the rider is traveling forward with their front foot on the nose to apply the initial force "pop".
In 1982, while competing in the Rusty Harris contest in Whittier, California, Rodney Mullen debuted an ollie on flat ground, which he had adapted from Gelfand's vertical version by combining the motions of some of his existing tricks. Mullen used a "see-saw" motion, striking the tail of the board on the ground to lift the nose, and using the front foot to level the board in mid-air. While Mullen was not initially impressed with his flat ground ollie, and did not formally name it, he realized it opened up a second, elevated plane on which to perform tricks.
The wheels of a skateboard are usually made of polyurethane, and come in many different sizes and shapes to suit different types of skating. Larger diameters (55–85 mm) roll faster, and move more easily over cracks in pavement and are better for transition skateboarding. Smaller diameters (48–54 mm) keep the board closer to the ground, require less force to accelerate and produce a lower center of gravity which allows for a better response time, but also make for a slower top speed and are better for street skateboarding. Wheels also are available in a variety of hardnesses usually measured on the Shore durometer "A" scale. Again like car tires, wheels range from the very soft (about Shore A 75) to the very hard (about Shore A 101). As the A scale stops at 100, any wheels labeled 101A or higher are harder, but do not use the appropriate durometer scale. Some wheel manufacturers now use the "B" or "D" scales, which have a larger and more accurate range of hardness. Modern street skaters prefer medium-sized wheels (usually 51–54 mm), as small wheels with lighter trucks can make tricks like kickflips and other flip tricks easier by keeping the center of gravity of the skateboard closer to the deck, thus making the deck easier to spin. Street wheels are harder (A 100/A 101). Vertical ramp or "vert" skating requires larger wheels (usually 55–65 mm), as it involves higher speeds. Vert wheels are also usually slightly softer (A 98/ A 99), allowing them to maintain high speed on ramps without sliding. Slalom skating requires even larger wheels (60–75 mm) to sustain the highest speeds possible. They also need to be soft and have better grip to make the tight and frequent turns in slalom racing. Even larger wheels are used in longboarding and downhill skateboarding. Sizes range from 65 mm to 100 mm. These extreme sizes of wheels almost always have cores of hard plastic that can be made thinner and lighter than a solid polyurethane wheel. They are often used by skateboard videographers as well, as the large soft wheels allow for smooth and easy movement over any terrain.
It is mainly because those items are guaranteed to help you familiarize yourself with the ins and outs of using them. They are a big help in making you feel comfortable when you push off with your feet while also balancing on top of the board when riding. It is not good to go for a very technical product, so it’s best to choose the mentioned types first.