The Seljuk Empire united the eastern Islamic world, and fought in the Second Crusade. The Seljuk Empire made several long lasting changes. These affected the region even after the empire was gone. Among them was making Farsi the language for history and events. They also shifted the center for the Arabic language culture from Baghdad to Cairo.
Central Asia
Central Asia is a region in Asia. The countries in Central Asia are Kazakhstan, Kyrgyzstan, Uzbekistan, Turkmenistan (which are mainly Turkic states) but also includes Tajikistan, and parts of China and Mongolia. Caucasia is also part of Central Asia. The United Nations also includes Afghanistan as part of Central Asia.
People have lived in the region of Central Asia since prehistoric times. Most of the region was part of the Silk Road. It was a part of the Persian Empire until Alexander The Great captured it. When he died, the land was given to his general Seleucus. Seleucus slowly lost it to the Parthians. When the Parthians (the Parthians were Persians) lost power, the Sassanids added it to their own Persian empire. However, a couple years later, during about the 600's A.D, Arab armies spreading the faith of Islam quickly captured it. A while later, an Iranian dynasty got semi- autonomy under the Abbasid Caliphate of Baghdad. They were known as the Samanids. The Samanids controlled most of Central Asia and Northwestern Iran. They had power over this area during the 10th century. With them, Central Asian cities, such as Bukhara and Samarkand, grew in culture.
However, Turkish armies from this area took the region away from them. They were known as the Seljuk Turks. At the same time, Timur captured it. After his death, the Timurids ( the name of the people of the dynasty Timur founded) could not hold unto their empire. They lost it to the Mongols. When the Mongols captured it, burned it to the ground. A while later, some rulers decided to make their own empires under that of the Mongols. These empires were known as Khanates. During the 19th century the Russian Empire conquered these lands. Many years later in 1991, all of the countries of Central Asia declared independence.
Uzbekistan has much cotton. Kazakhstan is rich because it has sold oil, gas and metals to Europe and China. Turkmenistan has adjusted better to independence from the Soviet Union than the other Central Asian countries, but it has been run by a dictatorship. Other than Kazakhstan, most of Central Asia are mostly underdeveloped.
Turkestan
Turkestan (Turkish: Türkistan, Kazakh: Түркістан, Uzbek: Turkiston, Turkmen: Türküstan, , Chinese: 突厥斯坦, literally "Land of Turks") is a region of Central Asia around the Caspian Sea and Aral Sea. Much of it is currently in China. During the 20th century, much of it was in the Soviet Union.
The main ethnic groups in the area are Turks, Chinese, Mongols and Persians.
Mesoamerica
Mesoamerica (literally, "central America") is a geographical region. It begins from around the Tropic of Cancer in central Mexico and ends near Costa Rica. The term is especially used to mean the native peoples and cultures that were there before the Spanish took over that region. The cacao tree is native to this area.
Cathode ray tube
The cathode ray tube or CRT was invented by Karl Ferdinand Braun. It was the most common type of display for many years. It was used in almost all computer monitors and televisions until LCD and plasma screens started being used.
A cathode ray tube has an electron gun. The cathode is an electrode (a metal that can send out electrons when heated). The cathode is inside a glass tube. Also inside the glass tube is an anode that attracts electrons. This is used to pull the electrons toward the front of the glass tube, so the electrons shoot out in one direction, making a cathode ray. To better control the direction of the ray, the air is taken out of the tube, making a vacuum.
The electrons hit the front of the tube, where a phosphor screen is. The electrons make the phosphor light up. The electrons can be aimed by creating a magnetic field. By carefully controlling which bits of phosphor light up, a bright picture can be made on the front of the vacuum tube. Changing this picture 30 times every second will make it look like the picture is moving. Because there is a vacuum inside the tube (which has to be strong enough to hold out the air), and the tube must be glass for the phosphor to be visible, the tube must be made of thick glass. For a large television, this vacuum tube can be quite heavy.
The cathode ray tube was invented in 1897, and used as an oscilloscope (a machine to show waves). Later, along with other inventions and improvements, it was used for the first modern electronic television by Philo T. Farnsworth in the 1920s. The CRT was the main type of television screen until the liquid crystal display became popular in the early 2000s.
Recitative
Recitative (Italian: “recitativo”) is music which is telling a story quite quickly, as if it were being spoken, "talky". The word means: “to recite” i.e. to tell a story.
Recitative is used in opera, oratorio and cantatas. When opera was invented around 1600 the composers needed to tell the story in music. In recitative the story is sung quickly, with maybe just a harpsichord playing a few chords. After a while, the situation in the story has changed, and the singer can sing an aria which is more interesting musically.
When recitative is just accompanied by a keyboard instrument it is called “recitativo secco” (dry recitative). Sometimes the orchestra joins this. This is called “recitativo accompagnato” (accompanied recitative). There are no bar lines in recitative because there is no regular beat.
Recitative is simple musically, it can sometimes describe the words being sung in quite interesting or amusing ways. Sometimes this might be improvised by the harpsichordist.
In the 19th century the difference between aria and recitative gradually disappeared. Wagner wrote operas where everything had musical interest and the various sections flowed into one another.
Ancient India
Ancient India had a long-lived civilization and culture. It covered several countries including modern-day India, Pakistan and Bangladesh.
The Indus Valley Civilization flourished from about 2600 BCE to 1900 BCE. It marked the beginning of the urban civilization on the subcontinent. It was centred on the Indus River and its tributaries. The civilization is famous for its cities that were built of brick, had a road-side drainage system and multi-storied houses.
During the Maurya Empire, founded in 321 BCE, most of the Indian subcontinent was united under a single government for the first time. Ashoka the Great who in the beginning sought to expand his kingdom, then followed a policy of ahimsa (non-violence) after converting to Buddhism. The Edicts of Ashoka are the oldest preserved historical documents of India, and under Ashoka Buddhist ideals spread across the whole of East Asia and South-East Asia.
Gupta, an important ruler during the Gupta period, was known as a wise and noble person.
Partition of India
The partition of India split British India into the countries of India and Pakistan (East and West Pakistan) in 1947. This partition was part of the end of British rule over the Indian subcontinent, called British Raj. The partition was caused in part by the two-nation theory presented by Syed Ahmed Khan, due to presented religious issues. Pakistan became a Muslim country, and India became a majority Hindu but secular country. The main spokesperson for the partition was Muhammad Ali Jinnah. He became the first Governor-General of Pakistan.
Millions of people moved across the new Radcliffe Line between the two newly formed states. The population of British India in 1947 was about 570 million. After partition, there were 370 million people in India, 170 million in West Pakistan, and 30 million people in East Pakistan (now Bangladesh).