A Japanese abacus (soroban) In the nineteenth and twentieth century, Asian government officials and scholars who visited the United States sometimes brought abaci as gifts. Some of these presents made ...

Many cultures used abaci or something similar (such as the Inca quipu). We chose to build two abaci from different cultures in order to compare them: the Russian (Schoty) abacus and the Japanese ...

Leonardo Fibonacci included it in his book "Liber Abaci." Once it was finally adopted, it paved the way for the concept of decimals, allowing mankind to advance its knowledge of mathematics and logic.

Similarly, your lips also have a moisture barrier, which often goes unaddressed. It can be easy to forget that, as Abaci notes, our lips are covered in top layers of skin until we're faced with an ...