Computers are very short-lived consumer devices. Whether they are phones, laptops, desktop computers or anything else that you have used as a computer you are going to have to replace them soon. The difficulty is that it is dangerous to simply pass along a computer that is filled with private information and even if you think that you have removed all of it there is a chance that you missed something or that they can recover the information. This makes preparing your used computer for sale vital and there are a number of ways that you can do this depending on the value of your data.
The first and easiest way to ensure that your data is gone is to do a fresh install of the operating system. Computers should come with a disk that provides the operating system and erasing everything and reinstalling it is not actually all that difficult and since you want the information gone it becomes even easier.
Where the first of these falls down is that it is possible for someone who actually wants to recover the data it is possible. Often when a hard drive is erased all that actually means is that the computer has been told it can write over the data, but until it has been written over it is really no different than it was before. The solution to this is to get one of the number of programs which can write over that data a number of times. This is effective against most people because you’re almost certainly never going to get all the data back, but there are programs that could potentially get some small amount which leads to the next level.
If you have something that is vital that no one ever see, or are just very worried about your privacy then you may want to consider something a bit more drastic. The easiest of these is simply to remove the hard drive. Hard drives are generally inexpensive and you may be able to pull out the one with your data and replace it with a fresh hard drive for very little. You can then install the operating system on that hard drive and be very sure that there will be no information passed along.
No matter whether you have used a computer for little more than browsing the web or have done banking on it there is a need to be careful when giving it to someone who could potentially steal passwords and even credit card information but with some basic though you should be safe.