* Nitrogen (N2): 78.08%

* Oxygen (O2): 20.95%

* Argon (Ar): 0.93%

These three gases make up over 99% of the atmosphere. The remaining 1% is composed of trace gases like:

* Carbon dioxide (CO2): A significant greenhouse gas, contributing to global warming.

* Neon (Ne), Helium (He), Methane (CH4), Krypton (Kr), Hydrogen (H2), Ozone (O3), etc.: Present in very small amounts but play important roles in various atmospheric processes.

It's important to note that the composition of the atmosphere can vary slightly depending on altitude, location, and time of day.