In its day, Homeworld was revolutionary. It had eye-popping graphics, very well done (real) 3D gameplay, and some of the best ambient music around.
For 30,000 years, your race (whichever one you specify; this is not made clear in the story) has been existing on a planet in the Kharak System. One day, the archaeologists were doing their thing, and they uncovered a stone with a galactic map etched in it, along with the remains of a massive ship. To them, this clearly meant that they were not home.
For 60 years, a Mothership that rivals in size to the first was being constructed. This brought about intense unity, planetwide. Everything was being done to further the construction of the ship. And it was finally ready. (On a side note: as one plays through the game, one never actually sees what the selected race looks like. Huh.)
Unlike many games of the RTS genre, Homeworld is the first of its kind to have movement in six directions, rather than just four. This includes up and down. With the introduction of these new directions, many more tactical formations can be accomplished, such as the sphere and the claw (think an X, stretched out to be 3D). Motherships and other large ships are also vulnerable from the top and bottom as well. However, I noticed that almost all of the gameplay takes place on the same plane, and there's almost no real reason for going up or down.
Unlike in a more standard RTS, like StarCraft, resources here are fairly rare. This problem is compounded by the fact that what one finishes a mission with is what the next mission begins with. This can be a problem if the resources were wildly spent (for example, in the first map of the game, there were only about 300 RUs around, equaling about 7 Scouts.). This means one can start a new mission with 5 RUs and a pair of scouts. It's time for a restart.
However, the game does provide a key unit to make up for these resource deficiencies: a Salvage Corvette (or two, three, or five) can capture an enemy ship and bring it back home for recontrolling. These Salvage Corvettes are wasted capturing small things like Scouts, but they pay dividends when going for the bigger stuff.
The units in Homeworld are the standard RTS fare, for the most part. There's weak and cheap Strike Craft (the Scout is one of these), the Corvette class which features slower moving, more expensive ships, the Frigate Class which is very powerful and can hyperspace around the map, and the Capital Class, which is a souped up version of the Frigate Class.
There's two races in Homeworld: the Kushan and the Taiidan. They're not enemies, rather, they are completely independent of each other. In the New Game screen, the player can select either one, and the only consequences are the shape of the Mothership (you like 'em really tall, or really flat?), and there's two special units availiable to each race. Other than that, they're identical.
The music in Homeworld induces a sense of loneliness, a perfect fit for a game like this. A couple of pieces sound like they'd make good ambience for a horror movie, and others will put one to sleep. It is still very good regardless, and Sierra has been kind enough to copy it into a seperate audio CD for listening while not playing Homeworld. (I think more games should do this.)
Overall, Homeworld is a very enjoyable game, only frustrating when there's a vast amount of units onscreen, leading to piles of lag, or when one must micro-manage the resources. Very fun, regardless.