Geology is the scientific study of solid Earth, though it can also refer to any other celestial body, the rocks of which it is composed, and the processes by which they evolve. It includes studying both the...

‘Practice’ is used as a noun. ‘Practise’ is used as a verb.

Gemstones are rare pieces of minerals that are found in the ground, which are then cut and polished to be used in jewelry and other decorative pieces. Crystals are pure substances whose atoms, molecules, or...

Plastic lenses are cheaper, lighter and less likely to break than glass. Glass lenses are more expensive, heavier and scratch resistant that plastic.

GDP is used to calculate all the products or services that are produced within a country’s boundaries and is a small part of the National income. On the other hand, national income is the sum of all the income...