19世纪三十年代，英国的库克和惠斯通开发了电报系统。该系统有五个磁针，通电后，可以指出一组字母和数字。
In the 1830s, the British team of Cooke and Wheatstone developed a telegraph system with five magnetic needles that could be pointed around a panel of letters and Numbers by using an electric current.
按照美国电报电话公司的新政策，使用数字用户线路（DSL）接连互联网的客户将受到限制，即每个月的下载量限制为150 G。
Under AT&T’s new policy, customers using digital subscriber line (DSL) connections to the internet will have a monthly download limit of 150 gigabytes.
20世纪晚期，在发达国家中，电报的大部分应用已被用计算机技术的数字数据传输系统取代。
By the late 20th century the telegraph had been replaced in most applications in developed countries by digital data transmission systems Based on computer technology.
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