Sun tries to give the appearance of being both a hardware company and a software company. That is a lie, however, since Sun is giving a lot of it’s software away for free (as in beer) now. That’s ok I suppose, if it’s used to drive hardware sales.
In other words, they are primarily a hardware company. Similar to Apple in that respect. Except Apple is rising in (desktop) market share, and Sun is declining (server market share).
Despite many years of trying to make inroads on the corporate desktop with thin clients and the misleadingly named “java desktop”, Sun really is all about servers. Servers mainly in heavy lifting roles (database) or internet facing (web server).
After the dotcom bubble 1.0 burst, there was such a glut of their hardware available on Ebay, as investors tried to get some pennies-on-the-dollar out of all those failed online petfood and similar ventures. Couple this with the rise of Linux plus the heavy backing of Linux by IBM, and Sun was hurting for hardware sales for many years. I don’t think they ever have recovered to anywhere near the pre-bubble sales even.