There are a few things that can cause a laptop to run slow. One reason is that the hard drive is full. When the hard drive is full, the computer has to work harder to access files, which can slow it down. Another reason is that the computer has a lot of programs running in the background. These programs can use up resources and slow down the computer. Finally, viruses and malware can also cause a laptop to run slow. These programs can take up space on the hard drive and use up resources, which can cause the computer to slow down. There are a few things that can be done to speed up a slow laptop. One is to clean up the hard drive by deleting unnecessary files. Another is to close programs that are running in the background. Finally you can run a virus scan to remove any viruses or malware that might be causing the computer to run slow.