Organic compounds that are made up of two kinds of atoms which are carbon and hydrogen.

Principal constituents of petroleum and natural gas.

Carbon atoms join together to create the framework of the compound, and the hydrogen atoms join them in various ways.

On Earth we can find them deeply buried in porous rock formations. The principal types of rock where we can find them are limestone, sandstone, and shale. The biggest source to get them is in the bottom of seas and oceans, this is because that is where we can find those rocks.

Oil and gas companies employ difficult techniques in order to extract them, this can be very damaging since the process requires drilling into the ground, affecting the habitat of many species and in case of accidents an immense pollution.