C: drive

Put Most Programs on the C: Drive

When you see a C: drive and a D: drive on your new Windows PC, you should put most programs/apps on the C: drive. It's the faster drive (especially if it's an SSD), and you will probably be loading and unloading with frequency. The second reason is that Windows often expects to find applications on the same disk as Windows. Reserve your less speed-critical "Data" for the D: drive, which might be a slower, spinning drive.