Main Difference
The main difference between Bag and Backpack is that the Bag is a simple tool in the form of a non-rigid container and Backpack is a bag carried on one’s back
Bag
A bag (also known regionally as a sack) is a common tool in the form of a non-rigid container. The use of bags predates recorded history, with the earliest bags being no more than lengths of animal skin, cotton, or woven plant fibers, folded up at the edges and secured in that shape with strings of the same material.Despite their simplicity, bags have been fundamental for the development of human civilization, as they allow people to easily collect loose materials such as berries or food grains, and to transport more items than could readily be carried in the hands. The word probably has its origins in the Norse word baggi, from the reconstructed Proto-Indo-European bʰak, but is also comparable to the Welsh baich (load, bundle), and the Greek βάσταγμα (bástagma, load).
Cheap disposable paper bags and plastic shopping bags are very common in the retail trade as a convenience for shoppers, and are often supplied by the shop for free or for a small fee. Customers may also take their own shopping bags to use in shops. Although, paper had been used for purposes of wrapping and padding in ancient China since the 2nd century BC, the first use of paper bags (for preserving the flavor of tea) in China came during the later Tang Dynasty (618–907 AD).
Backpack
A backpack — also called bookbag, kitbag, knapsack, rucksack, pack, sackpack or backsack — is, in its simplest form, a cloth sack carried on one’s back and secured with two straps that go over the shoulders, but there can be variations to this basic design. Lightweight types of backpacks are sometimes worn on only one shoulder strap.
Backpacks are commonly used by hikers and students, and are often preferred to handbags for carrying heavy loads or carrying any sort of equipment, because of the limited capacity to carry heavy weights for long periods of time in the hands.
Large backpacks, used to carry loads over 10 kilograms (22 lb), as well as smaller sports backpacks (e.g. running, cycling, hiking and hydration), usually offload the largest part (up to about 90%) of their weight onto padded hip belts, leaving the shoulder straps mainly for stabilising the load. This improves the potential to carry heavy loads, as the hips are stronger than the shoulders, and also increases agility and balance, since the load rides nearer the wearer’s own center of mass.
Bag (noun)
A flexible container made of cloth, paper, plastic, etc.
Bag (noun)
A handbag
Bag (noun)
A suitcase.
Bag (noun)
A schoolbag, especially a backpack.
Bag (noun)
One’s preference.
“Acid House is not my bag: I prefer the more traditional styles of music.”
Bag (noun)
An ugly woman.
Bag (noun)
The cloth-covered pillow used for first, second, and third base.
“The grounder hit the bag and bounced over the fielder’s head.”
Bag (noun)
First, second, or third base.
“He headed back to the bag.”
Bag (noun)
A breathalyzer, so named because it formerly had a plastic bag over the end to measure a set amount of breath.
Bag (noun)
A collection of objects, disregarding order, but (unlike a set) in which elements may be repeated.
“If one has a bag of three apples and the letter ‘a’ is taken to denote ‘apple’, then such bag could be represented symbolically as {a,a,a}. Note that in an ordinary context, when talking about a bag of apples, one does not care about identifying the individual apples, although one might be interested in distinguishing apples by species, for example, letting ‘r’ denote ‘red apple’ and ‘g’ denote ‘green apple’, then a bag of three red apples and two green apples could be denoted as {r,r,r,g,g}.”
Bag (noun)
A sac in animal bodies, containing some fluid or other substance.
“the bag of poison in the mouth of some serpents”
“the bag of a cow”
Bag (noun)
A sort of silken purse formerly tied about men’s hair behind, by way of ornament.
Bag (noun)
The quantity of game bagged in a hunt.
Bag (noun)
A scrotum.
Bag (noun)
A unit of measure of cement equal to 94 pounds.
Bag (verb)
To put into a bag.
Bag (verb)
To catch or kill, especially when fishing or hunting.
“We bagged three deer yesterday.”
Bag (verb)
To gain possession of something, or to make first claim on something.
Bag (verb)
To furnish or load with a bag.
Bag (verb)
To bring a woman one met on the street with one.
Bag (verb)
To laugh uncontrollably.
Bag (verb)
To criticise sarcastically.
Bag (verb)
To provide artificial ventilation with a bag valve mask (BVM) resuscitator.
Bag (verb)
To swell or hang down like a full bag.
“The skin bags from containing morbid matter.”
“The brisk wind bagged the sails.”
Bag (verb)
To hang like an empty bag.
“His trousers bag at the knees.”
Bag (verb)
To swell with arrogance.
Bag (verb)
To become pregnant.
Backpack (noun)
A hiking, or on a student’s back when carrying books.
Backpack (noun)
A similarly placed item containing a parachute or other life-support equipment.
Backpack (verb)
to hike and camp overnight in backcountry with one’s gear carried in a backpack
Backpack (verb)
to engage in low-cost, generally urban, travel with minimal luggage and frugal accommodations
Backpack (verb)
to place or carry (an item or items) in a backpack