Single vision lenses focus at only one distance. They may be designed for any distance from far vision, computer distance or for near vision. If they are designed for far vision your near vision may be good also if you are under forty years old. If older than forty you may need additional help at near. That might be bifocal lenses, progressive lenses or a different pair of single vision for near vision.
If your glasses are designed for near use your distance vision will be blurred and as you become older and need a stronger prescription the distance vision will become worse. At that point bifocals or progressive lenses may be a better choice.
Single vision lens designs are available in:
Transitions lens material
UV Blocking material
High Index lens material
Anti-Reflection coatings
Anti-Scratch coatings
Cosmetic tints
Sunglass tints