Money was originally created to serve as a substitute store of value to bypass problems with the barter system. If you had an apple tree but needed eggs, you needed to find someone with a chicken coop who wanted apples. ... More »

In a currency system, most items have a predetermined value, making transactions fast and standardized. When consumers know the cost of an item in advance, they can simply present the cash necessary to purchase the item.... More »

The Slinky's inventor, Richard James, was initially working on a device that would keep equipment steady on ships when he discovered the coil's unusual movements. James's creation is an example of an "accidental" inventi... More » History Inventions

The Internet was based on the idea of an "intergalactic network" of computers envisioned by J.C.R. Licklider in the early 1960s. However, no single person created the Internet. Shortly after this idea came to light, scie... More » History Inventions

The types of questions on a comprehensive fifth grade math test require the student to write and interpret numerical expressions, evidence understanding of the place value system and complete problems involving multi-dig... More » Education K-12 K-12 Curriculum

Bartering is a popular form of trade for individuals, families and businesses seeking to save money. Some small- and medium-sized businesses join bartering networks to exchange various goods and services. Barter networks... More »

Bartering involves exchanging goods or services for other goods and services without involving money. For example, a store owner giving a contractor store credit in exchange for carpentry work is an example of bartering.... More »