Well don't feel bad if you don't know what an LSO is or what it does. The long and short of it is that it's a special cookie that's stored in Flash not your browser. They've been around for a while now but they haven't gotten much attention from the press or even security companies. I find that interesting since they pose a far greater risk than regular cookies.
Worse still, not one of the browsers I'm aware of can be set to delete or block them. And to the best of my knowledge only one add-on for Firefox (BetterPrivacy found at http://ow.ly/1xbGn) exists to help control them.
Stranger yet is that not any of the security suites or programs out there makes any mention of them. Not Norton, not McAfee, not ZoneAlarm, not anybody in the security suit arena even so much as talks about them!!
Why is that such a big issue?
Well LSO's offer many, many, times the risk of regular cookies since they have several features that makes them special.
They can be up to 100Kbs in size for each site.
They aren't removed by your browser and have no expiration date.
They work and are stored even when a browser is in privacy mode (remember they work under Flash not your browser)
They're basically unknown by the public so sites feel free to use them as they choose and none mention them in their privacy statements.
So what we have is an open way for sites to track a person in great detail and without any control in place to stop it. Anytime we have something like LSO's it's an open invitation for abuse.
So what are your options?
First you could disable Flash but that would mean sites like YouTube wouldn't work. That's not an acceptable answer for most of us.
Second you can change Flash's settings to help control them. To do that you need to get under the hood in Flash but it's not really a hard thing to do. The complete instructions are located here on Adobe's site http://ow.ly/1xbZ3
And third you can use Firefox and the BetterPrivacy ad-on found here http://ow.ly/1xbGn
It is issues like LSO's that have made me a Firefox user. Not a single one of the other browsers has anywhere near the number or depth of add-ons that Firefox has.
So now the issue is will you allow sites to track you and monitor everything you do or will you take charge and get rid of the LSO's on your computer? Just remember big brother is watching, listening, and tracking everything you do on line as long as these LSO's remain in place.
For additional information Adobe's complete definition of what a Locally Shared Object (LSO) is can be found here http://ow.ly/1xccj