In the very early days of stock market trading, prices, quotes and other stock information was transmitted verbally or by written notice carried by a courier.
The inherent problems with this system are evident. One of the biggest is the potential for misinterpreting written information or for the courier to repeat the data incorrectly.
Either could lead to some serious problems for the person relying on the information for buying or selling particular stocks.
In the 1870s, the first mechanical means of transmitting information about the stock exchange was invented in the form of a stock ticker. If your business needed to be connected to the stock market for more instant information, you could do so by installing a stock ticker machine and then connecting it to the network of ticker machines.