Space Invaders was an old arcade game released by Taito way back in 1978. Midway licensed this title for release in the United States.
Space Invaders is the single most popular black and white arcade game ever made. Taito was officially the maker of this title, but it was so widely bootlegged, cloned, and ripped off, that you can find it under nearly 100 different titles on dozens of distinct platforms. I am not even going to attempt to list all of them here, but a few of the more common alternate titles are Jatre Specter, Cosmic Monsters, and Space King. Some of the alternates were exactly the same game as the original, while others were clones that were basically the exact same game implemented slightly differently. A few of the clones added new features like two player simultaneous action, while others (like Yosaku), were so different that you might not even realize that they are just another Space Invaders rip off.
This game has had six official sequels to date. They are, Space Invaders Part II, Space Invaders II, Return Of The Invaders, Super Space Invaders '91, Space Invaders DX, and Space Invaders '95. Americans also got Space Invaders Deluxe, which was simply Space Invaders Part II with a different title screen and a slightly different dedicated cabinet.
Chances are good that you already know how to play this game. But here it is anyway, just in case your local arcade never had a Space Invaders, and none of your friends ever had the best selling Atari 2600 version.
You control a little gun platform that can move left and right at the bottom of the screen. Your enemies are aliens who are aligned in 5 rows of 11 invaders each. The invaders move back and forth while dropping shots at you. They descend one rank each time they hit the side of the screen. You have to shoot them all, it is game over if they reach the bottom. There are 4 shields that you can hide behind, but they can be damaged by shots from you or the invaders, so you can't count on them for very long. Every once in a while you will see a UFO fly across the top of the screen, shoot it for a nice bonus to your score. A few of these details vary among clones, specifically the exact number of invaders and the shape and positions of the shields.
The last few invaders noticably speed up, and are rather difficult to hit. The game is endless, shooting the last invader simply brings on another screen full of them, with each screen starting closer to the ground than the last one. Well, they start closer up until a certain point, after that the game stops getting harder. Many people can actually play this game continually. Getting a truly remarkable Space Invaders score involves playing for hours and hours on end.
The various versions of Space Invaders came in a lot of different cabinets. I couldn't even begin to describe all of them, but I will at least talk about a few of them.
The upright version was blue and white and had painted sideart of several "werewolf" looking aliens, the "Deluxe" version had similar art, but in red and blue instead of blue and white. The control panel used a metal overlay and had buttons for movement and firing. Most non-US versions of the game had a 2-Way joystick instead of movement buttons. The monitor bezel and marquee were a single piece of glass with a nice detailed planetary scene. The monitors were supposed to have a set color overlays, but I haven't actually seen one that had them in many years.
The cabaret (or mini), version had woodgrain sides, and was almost completely unadorned.
There were many different cocktail versions made. I have seen Space Invaders in almost every type of cocktail table imaginable. Most of them used small 2-Way joysticks, and did not have a lot of decoration.
Clones and bootlegs were usually cocktails. Most 1970s era cocktails were simple rectangles with small control panels that were almost straight up and down. The exact designs varied a bit from manufacturer to manufacturer, but they all looked very similar. Upright clones and bootlegs were often conversions of earlier monochrome games such as Boot Hill and Shark JAWS.
Some versions of this game were actually in color, but most used plastic overlays to simulate color. These overlays were often misaligned on the machines, if not missing altogether.
Where to play
You can play Space Invaders almost anywhere. It has been widely ported, cloned, and emulated. There are many computer versions available, and the Atari 2600 port comes highly recommended. You may still see one of these out in the real world from time to time, but only at places that have "classic" games in addition to all their fighting games and redemption machines.
Space Invaders is a decent title to add to your arcade game collection. Prices seem to vary wildly on this one. My personal suggestion is to either get an original Taito/Midway one, or get one of the clones that used a color monitor. Getting one of the B&W clones will only make for future repair headaches, as you will be dealing with a strange boardset and a strange monitor. While getting an original only gives you the strange monitor to worry about, and getting a color one only leaves you with strange gameboards.