i want to know if there is a software which can film me through my built-in webcam and send it to another person pc or mail adresse by internet?im doutful my x husband install that on my laptop without my knowledge.
Unfortunately it is possible. If it was actually installed by someone with physical access to the machine most the malware scanners will not find it. Even simple remote desktop software will allow this and is hard to detect if you do not know where to look. There are also many bugs over the years in things like flash players that allowed access to cameras.
If you do not use the camera just go into the bios and disable it. That is almost impossible to bypass since you must be able to push keys at boot time to change it. Of course there is the low tech solution a piece of tape over the lens.