วันจันทร์ที่ 3 พฤศจิกายน พ.ศ. 2551

History of computer science

















The earliest known tool for use in computation was the abacus, and it was thought to have been invented in Babylon circa 2400 BCE. Its original style of usage was by lines drawn in sand with pebbles. This was the first known computer and most advanced system of calculation known to date - preceding Greek methods by 2,000 years. Abaci of a more modern design are still used as calculation tools today.
In
1115 BCE, the South Pointing Chariot was invented in ancient China. It was the first known geared mechanism to use a differential gear, which was later used in analog computers. The Chinese also invented a more sophisticated abacus from around the 2nd century BCE, known as the Chinese abacus.
In the
5th century BCE in ancient India, the grammarian Pāṇini formulated the grammar of Sanskrit in 3959 rules known as the Ashtadhyayi which was highly systematized and technical. Panini used metarules, transformations and recursions with such sophistication that his grammar had the computing power equivalent to a Turing machine. Between 200 BCE and 400 CE, Jaina mathematicians in India invented the logarithm. From the 13th century, logarithmic tables were produced by Muslim mathematicians.
The
Antikythera mechanism is believed to be the earliest known mechanical analog computer.[1] It was designed to calculate astronomical positions. It was discovered in 1901 in the Antikythera wreck off the Greek island of Antikythera, between Kythera and Crete, and has been dated to circa 100 BC.
Mechanical analog computer devices appeared again a thousand years later in the
medieval Islamic world and were developed by Muslim astronomers, such as the equatorium by Arzachel,[2] the mechanical geared astrolabe by Abū Rayhān al-Bīrūnī,[3] and the torquetum by Jabir ibn Aflah.[4] The first programmable machines were also invented by Muslim engineers, such as the automatic flute player by the Banū Mūsā brothers[5] and the humanoid robots by Al-Jazari.[6] Muslim mathematicians also made important advances in cryptography, such as the development of cryptanalysis and frequency analysis by Alkindus.[7][8]
When John Napier discovered logarithms for computational purposes in the early 17th century, there followed a period of considerable progress by inventors and scientists in making calculating tools.
None of the early computational devices were really
computers in the modern sense, and it took considerable advancement in mathematics and theory before the first modern computers could be designed.

ไม่มีความคิดเห็น: