As you are looking for homes, do you run across these three words and wonder what the heck is the difference? Several years ago I had the opportunity to speak with someone that deals in these types of homes, and here is a breakdown of the information he gave me.
Mobile and manufactured homes are the same thing. These homes are built indoors and have removable wheels and axles placed under them so they can be delivered to the home site and set down. The wheels and axles can remain with the home or not. The biggest indication that a home is a mobile or manufactured is that the structure under the home consists of a block towers that support the weight. These blocks will be under the middle portions of the house on the steel frame. Financing on mobile homes can be more tricky. Talk to your lender about options if you go this route.
Modular homes are completely different. In fact the only similarities between manufactured and modular homes is that they are built indoors and arrive on trucks. A modular home is built using the same specifications as a stick-built or frame house. The home is built indoors, and so elements such as wind, moisture, and temperature are not factors during construction. The other big difference is how weight is supported. A modular home must sit on a foundation around the outside edges of the home just like a stick-built or frame house. It will have either a crawl space or basement. Most lenders look at modular homes as the exact same thing as a stick-built home, and so borrowing money is generally much easier with a modular than with a manufactured home.
Hopefully this short comparison will help you as you are shopping and looking. I know it really helped me to know that there are differences and that the words mobile/manufactured, and modular are not interchangeable.