can someone please tell me what mal ware is? Nd what are rootkits? I'm new to this stuff

Wikipedia has a full discussion of both malware (http://en.wikipedia.org/wiki/Malware) and rootkits (http://en.wikipedia.org/wiki/Rootkit). Rootkits can be considered a specific type or class of malware. Both are undesirable software and usually difficult to remove. They also only primarily infect the Microsoft Windows family of operating systems.