computer games various platforms

[tali122]

some computer games are available on all platforms wheras others are limited to one or two- so how is this decided by , i assume , the publisher?

[bobjim1705]

It varies from case to case.
In some cases, a company (Microsoft/Nintendo/Sony) will pay for the exclusivity rights indefinitely, or for a certain length of time.
There's also the issue of sales. A lot (at least it seems like a lot) of games get published for everything but Gamecube. This is due in part to the comparatively lower software sales for Gamecube (except in the case of Soul Calibur 2).
And of course, there's practicallity. Games that require internet access are more likely to come out on PC and Xbox.
It's usually the publishers who will have to make the decision based on those facts.
Some companies are 'second party' devlopers and will develop games exclusively for that platform (e.g Rare and Nintendo in past years, now Rare and Microsoft.)

[Mobius1]

Well, technically Rare is now a Microsoft first party developer, since Microsoft doesn't part-own them, it completely owns them, despite them retaining their status as a separate entity. Much in the same way that Sony now owns Naughty Dog, the developers of Jak & Daxter games. Whilst they retain their individuality, they are first-party because they are wholly owned by Sony.

Second party would be companies like Insomniac Games (Spyro and Ratchet & Clank games) for Sony and, up until Metal Gear Solid Twin Snakes, Silicon Knights for Nintendo. Both of those developers stuck with a single company for a time, although that always seems to have been the case with Insomniac, Sony doesn't own them, and Nintendo didn't own SK.

[Space]

yes, the publisher decides which platforms the game will be available on.
Sometimes they don't have much choice ( if they're first-party ),
sometimes they just decide to go for the most popular console because it's less risky financially.
Sometimes they grant exclusivity rights to get a better deal.
Technical issues rarely have any importance, it's mostly politics and marketing.
PC games can be more profitable because publishers don't have to pay the royalties that apply for consoles. But then PCs are not as popular as consoles, and have bigger piracy problems.