Career Jumping

The world's most familiar video game character, Mario, has been in many professions over the years. In fact, he's been in several in just his first few years! He began in 1981 as a carpenter that had to save his girlfriend from a stupid ape called Donkey Kong. The next year, in the sequel Donkey Kong Jr., Mario kidnaps the ape as revenge while his titular son comes to save him. The year after that, Mario and his brother Luigi team up as plumbers to clear turtles, crabs, and flies out of pipes in the sewers in Mario Bros. In 1984, development had finished for Excitebike and Devil World on the Famicom. It was then that designers Shigeru Miyamoto and Takashi Tezuka began work on a prototype game that took place on a single-screen with a 16-by-32 pixel rectangle that didn't jump. Later, in a new prototype, they decided to expand on the concept by using large sprites like in Devil World, eventually redesigning the rectangle to feature Mario, citing the success of his latest arcade outing. This new sprite was considerably larger than the arcade game's, and as there was no Super Mushroom power-up yet, this was Mario's only size, and thus the official introduction of his "super" size. He also didn't shrink when taking damage, as evidenced by these eventually-unused death sprites for what would become Super Mario:

Nintendo's Land

Taking after Excitebike, Nintendo implemented a game engine with fast scrolling backgrounds that allowed the player to walk and smoothly increase momentum at will. This gave the game an element of strategy as they could either slowly and methodically plan out how they would advance, or they could run and jump through long stretches of the level.
According to the sketch below, level elements from the three arcade games were to be used in Super Mario Bros. These include Donkey Kong's conveyor belts, ladders, and girders; Donkey Kong Jr.'s ropes, logs, and springs; and Mario Bros.' frozen platforms and pipes. Eventually, they designed new elements or included variations of each in the game to make it stand out from the rest, be more original, and fit the levels' environments. And because of how plain Mario Bros. looked with a black background, Miyamoto decided to make it look more appealing by changing the color for some levels to blue.

Interpid Methods

Another major area that changed dramatically throughout development was Mario's moveset and methods of attack. Early on, the game was less about platforming and more about shooting. He would've used weapons like a rifle and a beam gun while riding a rocket. Later on, he was put on a cloud, as evidenced by this sketch:












Miyamoto's original plan was to design levels with mechanics depending on their settings, such as on the ground, in the water, and in the air. Having Mario fly around on a cloud in the sky levels was one example. The controls originally involved Up to jump and A to use an item in hand or kick if empty. Due to technical limitations and difficulties, this never came to pass. However, sky levels remained as places for Mario to collect coins when he climbs up a vine.

Screen Time

Miyamoto instructed Systems Research and Development to create levels that would last about a minute, citing that it takes about a second for Mario to run from one side of the screen to the other. SRD originally thought that meant making levels 60 "screen-lengths" long, but Miyamoto explained that there had to be some obstacles to slow the player down. This greatly shortened the levels down to 12 to 32 screens, but did save memory for more levels.

Save Some Bytes!

A common issue that the team ran into during development was the amount of memory they had to work with. They had to reuse certain graphics and sounds wherever necessary to conserve space for other things. That's why, for instance, bushes and clouds use the same graphics, where the only differences are the colors and placement on the screen. And when you take damage and go down a pipe, the sounds are the same.

A Super Power

In February 1985, the team finally implemented the world-renowned Super Mushroom, which spurred the game's name Super Mario Bros. They designed the levels to be completed by regular-sized "Small Mario", but felt it would be more exciting if Mario could grow using this new power-up. According to Miyamoto, the inclusion of the Super Mushroom was inspired by Japanese folklore where people eat magic mushrooms they find in a forest. This actually spurred the game world's name, Mushroom Kingdom. The idea was when the mushroom is freed from a ? Block, it moves. It was programmed to move slightly slower than Mario's max speed in the opposite direction to make it exciting to chase after. But it occurred to the team that when freeing something that resembles a Goomba from a ? Block, an inexperienced player's first reaction would be to run away from it. If a player were to try jumping over a Goomba to avoid it, they'd land on it and kill it. This would reinforce someone playing for the first time that the mushrooms are to be collected, and the Goombas are to be jumped on or avoided.