The magnetic compass always points towards north. The
earliest one was first used by the Chinese in about 1000 AD and came to be used
in Europe about 100 years later. The first compass was a magnetized iron needle
placed on a piece of cork or straw floating in a dish of water. The Chinese, in
about 100 BC, discovered that if spoons made of the magnetic mineral lodestone
were spun, they came to rest with the handles pointing in the same direction.
The reason was because the Earth’s magnetic field acted on the spoons like a
compass. The compass later developed from this observation. The compass we use
today was invented in 1200s. it consists of a pivoted magnetic needle on a card
with directions.
Friends you know a keyboard is the most important part of a computer. It consists of different sets of keys that help us to enter information into the computer. Today we will discuss about keyboard and its keys types and use. A standard keyboard has 104 keys. Types of Keys in a Keyboard: Alphabet Keys Number Keys Special Keys Function Keys Navigation Keys 1. Alphabet Keys: 26 alphabet keys are present on a keyboard from A to Z. these keys are not present in the alphabetical order. These keys are used to type words, sentences or paragraphs. 2. Number Keys: These keys are used for typing numbers. These keys are present above the top row of the alphabet keys and also present on the right side of the keyboard. 3. Special Keys: Keyboard has more special keys such as Space bar Key, caps lock key, backspace key, shift key, enter key, symbol keys and tab key etc. 4. Function Keys: 12 function keys are present on a keyb...
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