Final answer:
Opium is a narcotic from the opium poppy, highly valued by the British for correcting their trade deficit with China via smuggling, leading to the Opium Wars and significant Chinese concessions.
Step-by-step explanation:
Opium is a narcotic drug derived from the opium poppy. It was valuable to the British primarily due to its role in international trade with China.
During the 19th century, the demand for Chinese tea created a trade imbalance for the British, who did not have enough silver to trade with the Chinese.
The British East India Company cultivated opium in their colonies, particularly India, and smuggled it into China, where there was a high demand even though its recreational use was illegal.
This practice resulted in a reversal of the trade deficit as Chinese silver flowed into British hands, but also led to widespread addiction in China.
The escalating tensions between Britain and China over the opium trade led to the infamous Opium Wars, resulting in British victory and significant concessions from China, including the cession of Hong Kong.