According to Walk-In Dermatology, the main difference between the two types of skin marks is that moles are raised spots that occur singly or in clusters, and freckles are flat clusters of skin spots. WebMD relates that moles, which are clumped skin cells, can occur anywhere, including your scalp, under your fingernails or toenails, and even between your toes. Often moles appear as black or brown spots, and freckles are usually lighter. Occasionally, you're born with a mole, and sometimes you acquire them after birth. They can come and go over time, depending on the type of growth. While moles are typically raised or flat, if you have an atypical mole, it may have components that are both raised and flat. If you have an atypical mole, it can be cause for concern if it's itchy or irritating, which means you should get it checked out by your dermatologist.

While freckles rarely turn into skin cancer, moles, especially those with jagged or blurred edges, cause problems more frequently (via Walk-In Dermatology). If you want to reduce the appearance of freckles, you can achieve some lightening by reducing your sun exposure and using a broad-spectrum sunscreen with 50+ SPF. If you have any questions or concerns, be sure to talk to your doctor.