Symantec does post updates daily, but if you want them on a daily basis you have to go get them. If you use their "automatic update" system, they usually update on Wednesdays. They do occasionally send autoupdates more often if there's a specific threat for which a new signature needs to get out.

As pointed out by Jon, in addition to keeping your AV up to date, you do need to periodically check with Microsoft for Windows OS updates. If you use one of the more recent systems, XP, 2k, and I think for ME, you can get updates automatically. They will download them, in background, when you connect to the web, and will tell you when one is available. You still have to chose when (or whether) to install each of them.

I don't believe you can get auto update for Win98, and certainly not for Win95. There should be few of them, since Mickey announced that Win98 is considered "unsupported" almost two years ago, and will not write new updates unless there is an "incredibly critical" need for one. You should still check occasionally.

Since IE is an integral component of Windows, if you use Windows you should get updates to Internet Explorer regardless of whether you use it as your browser and regardless of what version of Windows you use.

Clarification: Adware is not considered a virus, since it doesn't replicate itself or attempt to send anything to anyone other than to the sites that put it there. It then reports data that it has "collected" by observing (usually) only what sites you've visited. Most of the frequently used adware does not identify what machine or user the information comes from.

Some adware does identify you and every site that you visit. For the most part, adware of this sort is found only in "download programs" for file sharing sites, and removing the adware will disable the program. If you read the privacy statement that was presented when you downloaded the software, you will find that by downloading their program you agreed to let them track everything you do - although often you have to follow links to other agreements "incorporated by attachment" to find this.

John