Calculator for example, solve quadratic equations symbolically. The first graphing calculator was the Casio fx-7000G released in 1985. The two leading manufacturers, HP and TI, released increasingly feature-laden calculators during the 1980s and 1990s. At the turn of the millennium, the line between a graphing calculator and a handheld computer was not always clear, as some very advanced calculators such as the TI-89, the Voyage 200 and HP-49G could differentiate and integrate functions, solve differential equations, run word processing and PIM software, and connect by wire or IR to other calculators/computers. The HP 12c financial calculator is still produced. It was
Electric Telegraph Company Electric Telegraph Company The Electric Telegraph Company was the world's first public telegraph company, founded in the United Kingdom in 1846 by Sir William Fothergill Cooke and John Lewis Ricardo, MP for Stoke-on-Trent. At creation the company purchased all the patents Cooke and Wheatstone had obtained to date. It merged with the International Telegraph Company in 1855 to become the Electric and International Telegraph Company. C.F. Varley was chief engineer in the 1860s. The company was nationalised by the British government in 1870 and BT, the giant multi-national communications corporation based in over 170 countries worldwide today, is a direct