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There are meteoroids, meteors and meteorites… so, what is the difference?
The “solid” part of Earth, covering the Crust and the Upper Mantle, is known as lithosphere. It is about 100 km thick. And it is made of rocks. All geological phenomena happen because of this rocky layer. How? Well, the lithosphere is broken up into tectonic plates, like slices. There are seven major and many minor plates on Earth. These plates move in relation to one another. And their movements lead to earthquakes, volcanic activity, mountain-building, and oceanic trench formation. This happens in three ways… They either move horizontally by gliding over asthenosphere, the layer below lithosphere, creating earthquakes and transform faults. Or they collide with each other at the plate boundaries, which produce earthquakes, volcanoes, mountain building and oceanic trenches. Or they may also move away from each other because of sea-floor spreading. So in a way, rocks are the main reason behind these geological phenomena! IN HISTORY Rocks are not only a part of our planet, but also of our history. Remember reading about the Stone Age in History books? Yes, the prehistoric time period during which human beings widely used stone for tool-making. 
The Stone Age covers the Paleolithic, the Mesolithic, and the Neolithic periods. It ends with the development of agriculture, the domestication of certain animals and the smelting of copper ore to produce metal. The tools were made from a variety of stones. For example, flint and chert were shaped (or chipped) for use as cutting tools and weapons, while basalt and sandstone were used for ground stone tools, such as quern-stones. Also, sediments (like clay) were used to make pottery. The shaping, chipping or flaking of stones for making tools is known as Flintknapping. And it is the world’s oldest documented profession. So, stone or rock is the beginning of technology, and its use in tool-making is the oldest art preserved in the archaeological record. IN ORES Most of the material that cannot be grown or created in laboratories and factories come directly or indirectly from rocks. How? Because these things are mined. And mining is the extraction of valuable minerals and other geological materials from earth, that is, rocks. Metals like iron, copper, gold, silver, and even non-renewable resources like coal and petroleum are extracted from rocks. All of us know the importance of mining for the advancement of human civilisation. So, realise how important rocks are? |
Rocks are part of history, and also, a witness of it. Human history is preserved in them. 
