Short answers, pulled from the story.
Company rule in India is variously dated from 1757, when the East India Company's victory at the Battle of Plassey gave it effective control of Bengal, or from 1765, when it was formally granted the diwani, the right to collect revenue in Bengal and Bihar. It ended in 1858 when the Government of India Act transferred authority to the British Crown following the Indian Rebellion of 1857.
The Battle of Plassey, fought in 1757, was the Company's decisive victory over Nawab Siraj-ud-Daulah of Bengal under the command of Robert Clive. The defeat of the Nawab and the installation of Mir Jafar, backed by the Company, gave the Company effective political control of Bengal and brought India into the public spotlight in Britain.
The Permanent Settlement of 1793 was introduced by Governor-General Lord Cornwallis and fixed land revenues in the Bengal Presidency in perpetuity. Rajas and taluqdars were recognised as zamindars obligated to collect rent from peasants and pay revenue to the Company at a fixed rate. In Bengal, that rate amounted to three million pounds at 1789-90 prices, reportedly twenty per cent above pre-1757 levels.
The Indian Rebellion of 1857 began on the 10th of May 1857 and spread largely through the North-Western Provinces and Oudh, drawing in almost the entire Bengal army. The scale of the revolt exposed the Company's inability to govern India without direct Crown authority. The Government of India Act 1858 dissolved the East India Company and transferred administration to the British government.
Between 1780 and 1860, India shifted from exporting processed goods such as fine cotton and silk, in exchange for bullion, to exporting raw materials including raw cotton, opium, and indigo, while importing British manufactured goods. By the late second quarter of the 19th century, opium alone constituted forty per cent of India's exports, driven by the Company's trade with Qing China.
W. B. O'Shaughnessy, a professor of chemistry at the Calcutta Medical College, conducted the first telegraph trial in India in 1851, running a line from Calcutta to Diamond Harbour using a galvanoscope of his own design. By February 1855, over 3,050 miles of telegraph lines connecting Calcutta, Agra, Bombay, Peshawar, and Madras had been completed, and by 1857 the network extended to 4,555 miles.