A backpack—also called knapsack, schoolbag, rucksack, rucksac, pack, sackpack, booksack, bookbag or backsack—is, in its simplest frameless form, a fabric sack carried on one's back and secured with two straps that go over the shoulders, but it can have an external frame, internal frame, and there are bodypacks. In the era of more and more individuality, various styles such as simplicity, retro, and cartoon also cater to the needs of fashion people to show their individuality from different aspects. The styles of luggage have also expanded from traditional business bags, school bags, and travel bags to pencil cases, coin purses, and small sachets. 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.
A daypack is a smaller, frameless backpack that can hold enough contents for a day hike, or a day's worth of other activities. They are not large enough for average wilderness backpacking that use full-sized sleeping bags and backpacking tents, but may be large enough for ultralight backpacking. Padded or unpadded waist straps may be provided to distribute weight across the body. In many countries, backpacks are heavily identified with students, and are a primary means of transporting educational materials to and from school. In this context they are sometimes known as bookbags or schoolbags. The purchase of a suitably fashionable, attractive, and useful backpack is a crucial back-to-school ritual for many students. Typical school backpacks generally lack the rigid frame of an outdoor-style backpack and include only a few pockets in the front in addition to the main storage compartment. While traditionally very simple in design, school backpacks are often made with padded shoulder straps and backs as well as additional reinforcement to hold large numbers of heavy textbooks, as well as safety features such as reflective panels to make the wearer of the pack more visible at night. Backpacks are sometimes worn as fashion accessories, in which they perform the same function as a purse. Some such backpacks designed specifically for women are no larger than a typical purse, and are generally associated with younger women.
Some backpacks are specifically designed to carry certain items. Common examples include backpacks for small valuable items such as laptops and cameras; backpacks designed to hold laptop computers in particular generally have a padded compartment to hold the computer and medium-sized pockets and flaps to accommodate accessories such as charger cables and mice. These are especially common in college and university settings. In order to supply these devices with electricity, a few high-end backpacks are equipped with solar panels. The global computer bag giant HTTP company launched the world's first backpack in the 1980s. Due to the use of shock-proof protective materials, plus special ergonomic design and unique reinforcement, it is extremely durable and very popular. In addition to the shock-proof protective compartment specially used for holding the computer, the computer backpack also has a considerable space for small items such as luggage. Many high-quality computer backpacks are also widely used as sports travel bags.
A travel bag refers to a type of bag prepared for travel or tourism. It is a kind of bag that can pack daily necessities or anything you want to take with you for easy portability when you leave your hometown for a long trip, or do things or visit, or devote yourself to nature and enjoy the sun and rain. Travel bags can be divided into backpacks, handbags and drag bags. Size and style need to be considered when choosing a bag, in addition to factors such as the user's size and shape and weight-bearing capacity. Because outdoor travel bags are used in special environments, higher requirements are placed on the materials and craftsmanship of travel bags. All the places where the travel bag is stressed are back-stitched three times with stitches, making the stressed places sturdy and durable. The buckles and other parts of the travel bag can be frost-proof, smash-proof and deformed at 120 degrees Celsius without damage. The outer materials of the travel bag are mainly 420D Oxford nylon, 1000D nylon, 600D or 1000Dpolyester (polyester), or 1000D CORDVRA and other materials. The 1000D material has high density and is very wear-resistant, making it very suitable for field use. CORDVRA is a well-known high-grade wear-resistant nylon roving fabric developed by DuPont in the United States. The material's abrasion resistance is much higher than that of ordinary nylon or polyester, and it is lightweight. More than 90% of the world's famous brand travel bags are made of this prestigious nylon material. These materials can withstand water pressure of 0.5m~2m, keeping the contents of the bag dry. Some materials also have a tear-proof function. Once punctured, the breach will not be torn apart and expanded. Canvas is also widely used in the manufacture of travel bags, and Canvas Republic is a typical example. Because canvas is more wear-resistant and has a high density, it has a rainproof effect, and the texture is very soft, so it is very popular.
In American English, a gym bag or carryall is a large bag made of cloth or leather typically with a rectangular base and a zippered opening at the top. Two handles enable the bag to be carried, and a (usually removable) strap lets the user support the bag on the shoulders. In British English, the same kind of bag is called a sports bag. A holdall (or occasionally hold-all) may be a similar bag but may often have wheels and possibly a telescopic handle. The term covers a wide variety of types of bag. A holdall is often used in place of a suitcase or for carrying sports equipment, and has the advantage over most suitcases of being compressible when empty.
Tool bag is a bag for people to store various tools in life. It can store hardware tools, garden tools, maintenance tools, testing equipment, electrician tools, vehicle tool bags, power tool bags, telecommunication tools, etc. It has powerful functions for storing various tools. It is easy to carry, and the access layout is scientific and reasonable, which helps users to complete work tasks faster, better, safer and more conveniently. Sometimes some functional software tools are packaged as software packages. The tool bag is a bag suitable for laborers that has emerged in recent years. It has a wide range of applications, suitable for hardware workers, and also suitable for cleaning service industry. It is also suitable for students. In the past, the style of the tool kit was monotonous, the design was simple, and the price was cheap, and ordinary fabrics were generally used for simple sewing. The demand for toolkits from all walks of life is also subdivided. The product design is novel and unique, and it is specially designed and produced for the needs of specific industries and specific industries. Tool kits are basically made of 600D waterproof Oxford cloth, but also 1680D, 1800D and other thickened waterproof Oxford cloth, and Oxford cloth can also be made of special fabrics (such as anti-static, environmentally friendly fabrics, etc.).
A cooler bag is a type of thermally insulated shipping container in the form of a bag which can be carried, usually made of thermally insulating materials and sometimes a refrigerant gel. It is used to help maintain the temperature of its contents, keeping cold items cold, and hot items hot. Insulated bags have been in use for many years in industry, medical/pharmaceutical use, food delivery, lunch bags, etc. Several designs have been available. Thermal pharmaceutical bags are designed to transport temperature-sensitive medications, protecting them from damaging temperatures, shocks, and light. Many vaccines are delicate biological substances that can lose part or all of their effectiveness if they are frozen, allowed to get too hot, or exposed to bright light. Such vaccines must be kept within a specified temperature range, typically 2 to 8 °C (36 to 46 °F), from manufacture to use. According to the World Health Organization, at least 7% of temperature-sensitive medical products suffer significant degradation in potency in transit.
