Most people entering the construction industry learn a specific craft through: An apprenticeship program
What is the context of the question? With all that you have provided my best guess would be "computational function/solving"
Blaster Worm., the worm has been designed to tunnel into your system and allow malicious users to control your computer remotely. A Trojan horse is not a virus. It is a destructive program that looks as a genuine application. Unlike viruses, Trojan horses do not replicate themselves but they can be just as destructive.
