The most common reason for a computer running slow is a program is running in the background and hogging all the 'resources' the computer needs to operate efficiently. These resources include memory, CPU (Central Processing Unit) resources, hard drive space and more. When you start your computer in the morning the first item to load is the BIOS (Basic Input / Output System). This system loads up so that computer memory, the hard drive and more can be accessed. Next, the bootstrap loader fires up the OS (Operating System). The OS loads all sorts of programs it thinks it might need into memory. The OS is responsible for managing the CPU, memory, devices and more. It's a very busy system. Sometimes it may load too many programs into memory and over-extend the capacity of the computer. At other times a device such as the computer's GPU (Graphical Processor Unit) may be taking up too much memory.
To see if your computer is overloaded open Task Manager by hitting Ctrl-Alt-Delete and choosing Task Manager. When Task Manager opens it is generally on a simple view. Choose More details to see an expanded view of what your computer is up to. You'll see a number of rows and columns. We're concerned with the columns first and the rows second. The CPU column shows us how busy our computer's processor is. The Memory column displays how much computer memory is currently in use. Disk tells us how much our computer's hard drive is being accessed and Network is the percentage of network utilization. If one or more of these columns is above 85% our computer will be noticeably slower than usual. The rows tell us what application or background process is using the most resources. You can sort the view by clicking any column you choose. To stop an application or background process that is using too many resources simply right-click the program / process and choose End task.
The second most common reason our computer's run slow is we have too many programs open. The solution to this problem is easy: simply close some programs you're not using.