Courier services are usually meant for packages that are 150 lbs or less. Examples of companies that provide courier services include FedEx, UPS, DHL, Purolator, TNT, Loomis, and Canpar. The main advantage of courier services are that they are extremely fast and efficient, provide routine customs clearance, and almost always provide you with the convenience of door to door service.
Freight service are usually meant for larger shipments - shipments in excess of 150lbs. The service is not nearly as quick as courier service nor is arranging the transportation however, it is actually the most cost effective way of shipping locally or cross country.
There are different types of freight services - Air, Ocean, and Truck. The most common one being truck load freight services.
If you are shipping a skid or pallet via truck freight, this is often known as shipping LTL - Less than truck load. For those that fill up an entire truck with their goods, they are known to be shipping FTL - Full truck load. LTL or FTL services are usually door to door.
Air freight and Ocean freight are usual airport to airport or port to port however some are able to extended their delivery range.