Alkanes contain only single bonds between carbon atoms and between carbon and hydrogen atoms. These are called covalent bonds, where atoms share electrons to achieve a stable electron configuration.

Here's a breakdown:

* Carbon-Carbon bonds: Each carbon atom shares one electron with another carbon atom, resulting in a single covalent bond.

* Carbon-Hydrogen bonds: Each carbon atom shares one electron with a hydrogen atom, also forming a single covalent bond.

This simple structure makes alkanes relatively unreactive compared to other hydrocarbons.