ABACUS

Abacus = 算盤, 用 Abacus 學習則叫作珠心算, 而市面上的 Abacus 學習方法是指利用利指代替算盤去計加減乘除 (除數已是盡頭), 背熟口訣, 學習純熟以後便可以在腦裡完成所有算盤運算, 從而達到快而準的計算, 亦因為是用算盤式的計算, 純熟後真的可以快過計數機 (只是根據數據, 能做到這個程的學生不會超過千分之一).

An abacus is a calculation tool, often constructed as a wooden frame with beads sliding on wires. It was in use centuries before the adoption of the written Hindu-Arabic numeral system and is still widely used by merchants and clerks in the China, Japan, Hong Kong, Africa, and elsewhere.

Origins
The origins of the abacus are disputed, as many different cultures have been known to have used similar tools. It is known to have existed in Babylonia and in China, with invention to have taken place between 1000 BCE and 500 BCE. The first abacus was almost certainly based on a flat stone covered with sand or dust. Lines were drawn in the sand and pebbles used to aid calculations. From this, a variety of abaci were developed; the most popular were based on the bi-quinary system, using a combination of two bases (base-2 and base-5) to represent decimal numbers.

The use of the word abacus dates back to before 1387 when a Middle English work borrowed the word from Latin to describe a sandboard abacus. The Latin word came from abakos, the Greek genitive form of abax ("calculating-table"). Because abax also had the sense of "table sprinkled with sand or dust, used for drawing geometric figures," it is speculated by some linguists that the Greek word may be derived from a Semitic root, ābāq, the Hebrew word for "dust." Though details of the transmission are obscure, it may also be derived from the Phoenician word abak, meaning "sand". The plural of abacus is abaci.

Chinese abacus
Main article: Chinese abacus
The suanpan (Simplified Chinese: 算盘; Traditional Chinese: 算盤; pinyin: suànpán, lit. "Counting tray") of the Chinese is similar to the Roman abacus in principle, though has a different construction, and it was designed to do both decimal and hexadecimal arithmetics.

The Chinese abacus is typically around 20 cm (8 inches) tall and it comes in various widths depending on the application. It usually has more than seven rods. There are two beads on each rod in the upper deck and five beads each in the bottom for both decimal and hexadecimal computation. The beads are usually rounded and made of a hard wood. The beads are counted by moving them up or down towards the beam. The abacus can be reset to the starting position instantly by a quick jerk along the horizontal axis to spin all the beads away from the horizontal beam at the center.

Abacus = 算盤, 用 Abacus 學習則叫作珠心算, 而市面上的 Abacus 學習方法是指利用利指代替算盤去計加減乘除 (除數已是盡頭), 背熟口訣, 學習純熟以後便可以在腦裡完成所有算盤運算, 從而達到快而準的計算, 亦因為是用算盤式的計算, 純熟後真的可以快過計數機 (只是根據數據, 能做到這個程的學生不會超過千分之一).

算盤的教學理念是 -- 人的腦部還有很多部份需要開發, 所以透過練習快速心算, 就能開發腦部, 不過根據腦部專家的建議, 要開發腦部應該從多方面努力, 包括數學, 語言, 運動, 說話等不同方面, 這樣更有效開發腦部.

要留意一點, 因為珠心算有自行的一套計算加減乘除的口訣, 有別於我們學習加減乘除的學習方法, 一旦學生在中途追不上, 要停學的話, 學生的加減乘除 (特別是加法) 會出現很大的混亂, 即學生不知道應該用什麼方法, 很多學生都是見證人之一.

abacus ( 算盤 )

abacus = 算盤