The 2 main functions of a moisturizing lotion are:
1) To lock-in (conceal) hydration (water) into the skin.
2) To create a protective barrier between your skin, the environmental pollution and other irritants.
〉 Types of facial moisturizers :
Typically oil-free moisturizers formulated with a high concentration of water. These products can be interesting because they provide intense and instant hydration to dry skin. However, these light formulas do not create a barrier as effective as a cream (containing oil) in order to lock in moisture. Therefore, they can end up drying out your skin, especially in winter conditions. This is why I recommend those products for summer and high humidity levels.
Due to their absence of oil, they also don't protect your skin as much as a regular cream from the environment. This is why, despite the hype surrounding oil-free products, I usually like to apply a more concealing cream (or sunscreen) afterwards. Powder foundation will help with the potential oily look.
Typically a mixture of water, emollients and oil. These products provide hydration (water) as well as a protective barrier to your skin thanks to the oil they contain. Creams vary greatly from lighter to thicker, find the right one for you!
In general, I don't advise to invest big money on creams, especially if you are on a tight budget. The most effective way to provide active ingredients to the skin is through serums applied under your moisturizer. The cream is mostly here to lock in the previous products and to provide a protective barrier. What you should be looking for are non-irritating, simple (short ingredient lists) and fragrance-free products. Avoid mineral oil and petroleum-derived ingredients as they clog skin.
Facial oils can be used instead of a moisturizing gel or cream. Those worried about preservatives and chemical ingredients tend to prefer pure organic oils. Applied in a reasonable manner, they provide an effective protective barrier for the skin. What's really interesting with those products is that they are a great way to nourish and repair skin, as they provide essential fatties (omega 3 and 6) and some antioxidants. But lacking water, pure oils provide no actual hydration at all by themselves.
You can find pure organic cold-pressed carrier oils in health stores (jojoba oil, rose hip oil, ...) or buy a blend of different oils from an actual skincare company.
MY TIP - Mix in a few drops of facial oil (like pure rosehip oil) to your moisturizing cream at night. Doing so will probably create the best sleeping mask you could ever hope for. You should wake up with a glowing and visibly nourished skin. It's a great way to repair a damaged skin barrier. It also thickens a moisturizer making it more occlusive, so it retains more moisture.