A rug can be picked up and moved to another location, carpet is permanently installed.
it is a piece of fabric, generally a carpet type with a loop or pile that is used as a floor covering( unlike a carpet it is not attached to the floor and is movable), it can also be made out of heavy braided cotton fabric or even recycled plastic bags. also, in american slang a rug will also refer to a man's hairpiece or toupee
In UK Rug means: Small loose carpet i.e. used in front of fireplace (large carpet that is not fitted is a carpet square) Travelling blanket (called travel rug) Hairpiece for men
I would say that a rug is a peice of carpet that can be moved from one area to another, such as an area rug. Typically, you'd use an area rug in a living room (under a coffee table) or in a dining room (under the table) or other various places. A mat would be like a door mat (indoor or outdoor) or a bath mat. Carpet would typically be installed and unable to be moved from one area to the next.
3. Always refer to a Rug for pieces measuring 5'x8' or less, and a Carpet as 6'x9' and over. Like to get more technical? A rug measuring less than 3 feet in width and over 6 feet in length should be considered a runner. A carpet measuring 3 foot to 4 foot wide and over 7 feet long should be termed as a wide runner. A carpet measuring 4 feet to 5 feet wide and over 10 feet long is considered a Gallery Runner. A round rug is called a round, a square rug is called a square.
