Hi, I'm a new member, if I'm writing to wrong section, please move it. And my native language is not English, please let me know if I can't describe something thoroughly.
Here is my problem: I think my PC is being monitored. Though its just a doubt I still want to be sure. I read a lot of things about monitoring on web, but I couldn't get an exact answer. I think there are a few ways to monitor a PC.
I read that if there is trojans or malwares etc. in my computer, my passwords can be stolen. How can i be sure if there is anything like this in my computer?
I don't think I'm being watched with some kinda device(not sure if its called device) that is attached to my computer. Because I think I'd notice that. But if there is a device, how can I know that?
Thats kinda complicated for me to explain, please tell me if you don't understand what I'm saying

. There is a router in my house and 4-5 laptops are connected to it. I mean, no computer is directly connected to internet cable, we connect from the same network, we share the connection. Sorry I don't know what that is called in English, perhaps "wireless". So, is it possible to watch any of the laptops because we share the same connection? I read that the admin computer can watch the other computers. But couldn't get what that means. Please explain to me

. And which one is the admin computer since there arent any laptops which are directly connected to router/cable.
I'm not sure it its the right thread to ask this(because its not about monitoring) but anyway... I live in flat and our neighbors can see our network connection from their computer. But they need to know the password to connect our network. If someone gets the password somehow, and uses our network, how can I understand that?
I read there are lots of monitoring programmes, Spytech for example. How does they work? It must be downloaded to the PC you want to monitor right? If that sorta programmes are downloaded to my PC how can I notice that?
And lastly, if someone knows my IP address, can he/she watch my computer? I read that there are programmes about it. You download it and write someones IP address and then you can monitor his/her computer. But that sounded a bit weird to me, is it true or not?
By the way I'm using "Windows Vista Home Premium", not sure if that info is needed though

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