What are hydrocarbons?

Hydrocarbons are the organic compounds which are only composed of carbon and hydrogen. Hydrocarbons are of different types like aromatic hydrocarbons, alkanes, alkenes, and cycloalkanes. Down below are some examples illustrating different types of hydrocarbons.
ALKANES
The hydrocarbons in which all the valancies of carbon atoms are satisfied by single covalent bonds only are called alkanes. For example, methane
As you can see that all the 4 hydrogens are bonded to 1 carbon atom with the help of a single covalent bond.
ALKENES
The unsaturated hydrocarbons which are having atleast 1 carbon- carbon double covalent bond are called alkenes. For example, PROPENE
As you can see in the image above 2 carbon atoms are bonded with each other with a double covalent bond and the remaining valancies are satisfied by single covalently bonded hydrogen atoms.

ALKYNES
The unsaturated hydrocarbons in which atleast 1 carbon- carbon triple covalent bond exists are called alkynes. For example, PROPYNE
As you can see that 2 carbon atoms are bonded with each other by the help of a triple covalent bond and the remainig valancies are satisfied by single covalently bonded hydrogen atoms.