Major Gases:

* Nitrogen (N2): 78.08% - Nitrogen is the most abundant gas in the atmosphere, and it plays a crucial role in plant growth.

* Oxygen (O2): 20.95% - Essential for respiration and many other biological processes.

* Argon (Ar): 0.93% - A noble gas with little chemical activity.

Trace Gases:

* Carbon Dioxide (CO2): 0.04% - Plays a vital role in the greenhouse effect, regulating Earth's temperature.

* Neon (Ne): 0.0018% - A noble gas.

* Helium (He): 0.0005% - A noble gas.

* Methane (CH4): 0.00018% - A greenhouse gas, contributing to climate change.

* Krypton (Kr): 0.00011% - A noble gas.

* Hydrogen (H2): 0.00005% - The lightest element.

* Ozone (O3): 0.000004% - A powerful absorber of ultraviolet radiation, protecting life on Earth.

* Water Vapor (H2O): Variable - The amount of water vapor in the atmosphere varies greatly depending on location and weather conditions.

Other Gases:

* Xenon (Xe): Trace amounts.

* Nitrous Oxide (N2O): Trace amounts - A greenhouse gas.

* Sulfur Dioxide (SO2): Trace amounts - A major air pollutant.

* Carbon Monoxide (CO): Trace amounts - A poisonous gas.

It's important to note that the percentages of these gases can vary slightly depending on location and altitude.