A refurbished computer is a second hand machine that has been improved to make it work better. Sometimes, a refurbished PC or laptop will be as good as new. Other times, you may still be getting an older model that is ageing and is inevitably going to be a little bit slower.
If you need to buy a new computer and cannot afford a new one, it is a good idea to choose a refurbished model. Make sure you buy from a reputable seller, and that you have a good length of guarantee on the equipment you purchase.
The danger with a refurbished machine is that you can never quite tell what has been done to it. There is always the danger that something will go wrong, which is why it is so essential to protect yourself with a guarantee. Buy from a reputable seller and ask to use the computer first.