Soft lighting
Soft lighting has a very widespread grey zone shown in the photo. It is used more commonly in portrait photos because it doesn't show blemishes or any harsh shadows like hard lighting. The softer the light is the more grey zone and vise versa. The size of the light is the most important aspect of the photo in regards to how soft you want the image. Therefore you want the lighting closer to your subject if you want a softer light and you angle the light to show less shadows and blemishes. In portrait photos where you aren't provided the official tools for making light more spread out, such as umbrellas or light boxes, most photographers tend to set up the focus of the image on or against a wall which causes a bounce of light from the flash off the walls to make the light appear larger. Some examples and comparisons are down below.
My own images
Butterfly lighting
Loop lightng
Side profile
Rembrandt lighting
Rim lighting
Split lighting
My own personal profile in rembrandt lighting
Photos edited in photoshop