A computer virus is a malicious software program loaded onto a user's computer without the user's knowledge and performs malicious actions. It can self-replicate, inserting itself onto other programs or files, infecting them in the process.
We use analog and digital signals in our everyday lives with the radio, the cell phone and with our own computers. our computers and our cell phones are all digital now but radio's are still considered analog. Radio telescopes explore space by using radio waves and signals to almost like scan space and collect data like a sonar in a submarine.
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Ok if lets say a young child at the age of like 6-7 was allowed to play grand theft auto by his/her parents maybe the child would understand incorrectly and start doing what the people do in the game this may cause to serious trouble jail time or even death. In this case dont let your kids play underrated games or watch underrated movies.
Hope that helped you understand more.