You won't believe how difficult it is to give a proper description to any game hit. I'll try anyway.
The first time I met Mario Bros. on your console Dendy. It was the mid-90s, the game was part of some unnamed collection, and against the background of the library that was at the disposal of Nintendo / Dendy lovers at that moment, it looked unpretentious. A-la played 10 minutes and forgot. I played it longer until I bought a second cartridge for the console.
Mario Bros. combines strategic elements, but without gaming skills and proper dexterity is a tough nut to crack. This is primarily a platform jumper-begalka. The entire playing space consists of a single screen. Platforms (that's where the name of the genre comes from) are arranged like in the game Joust. Mario and Cousin Luigi can jump on them, climbing higher, or running away from turtles, crabs and bugs. Yes, I almost forgot the most important thing. The animals fall out of the pipes, and slowly moving down, down and down the platforms. Mario should bounce, hitting his head on the platform below them. This confuses them. You can play together.
I have seen many versions of this game and I will say that the Atari 5200 edition looks decent. Mario looks strange, with a small head, but in general, they tried to translate the graphics as much as possible. Despite its simplicity, the game is replete with small but nice details. The turtle, if it lies on its back for a long time, crawls out of the shell and then puts it on, the mechanics of the crab claws are adequately animated and voiced.
Briefly on the versions:
Atari 5200: the most unusual edition of Mario Brothers, but not the worst.
Atari 7800: even though the game is closer to the original than the 5200 version, I didn't like it at all. All the elements of a normal game are present, but it was worth working on the animation more. It doesn't feel like you're playing "Mario"!
Nintendo (NES): Almost arcade-quality Mario Brothers game (missing intro demo).