You can not really tell if your computer is safe but the things that someone can do is to try their best to keep their computer from getting attacked. A good example is to put anti virus on the computer keeping it safe from the different types of malware that can effect the computer. This is one of the best ways to keep malware away. Another thing that someone can do is to make sure that they know who is using their computer and what are the different websites that they visit and what things they are dowloading. I learned this because as a kid i used to download songs off of random unsafe mp3 converting websites to get the songs for free. But little did i realize that i was getting a virus every time i was downloading a song. This became a habit and it got to the point where the pc was no longer usable. we would turn the computer on and there would be a bombardment of popups. This can help prevent the computer from getting unwanted downloads. So now on my pc i have a download password on it so that no one can download anything without my permission. This keeps my pc running and clean and free of the different viruses. One more thing that someone can do to keep their computer safe is to make sure to only visit https websites which are the secure websites. This will also keep the pc from getting the different harmful malwares of the many unsafe websites there are on the world wide web. So in conclusion, you can not tell if your computer is safe or unsafe but what you can do is to keep things away from the computer to keep the computer safe from everything.