Igneous rock (derived from the Latin word ignis meaning fire) is one of the three main rock types, the others being sedimentary and metamorphic rock. Igneous rock is formed through the cooling and solidification of magma or lava. Igneous rock may form with or without crystallization, either below the surface as intrusive (plutonic) rocks or on the surface as extrusive (volcanic) rocks. This magma can be derived from partial melts of pre-existing rocks in either a planet's mantle or crust. Typically, the me..
Thermodynamics is a branch of natural science concerned with heat and its relation to energy and work. It defines macroscopic variables (such as temperature, internal energy, entropy, and pressure) that characterize materials and radiation, and explains how they are related and by what laws they change with time. Thermodynamics describes the average behavior of very large numbers of microscopic constituents, and its laws can be derived from statistical mechanics.
The slash ( /), also known as a stroke and by the technical term solidus, is a sign used as a punctuation mark and for various other purposes. It is often called a forward slash, a retronym used to distinguish it from the backslash ( \). It has many other names.
The comma , form the Greek κόμμα komma, is a punctuation mark, and it appears in several variants in various languages. It has the same shape as an apostrophe or single closing quotation mark in many typefaces, but it differs from them in being placed on the baseline of the text. Some render it as a small line, slightly curved or straight but inclined from the vertical, or with the appearance of a small, filled-in number 9. It is used to separate parts of a sentence such as and lists of three or mo..