The Three Rs
The three Rs of environmentalism are a good guide for how to reduce your impact on the earth. Reduce means buying less and using what you have longer; reuse is using something again instead of throwing it away; recycle means turning old materials into new ones. This can be as simple as reusing a plastic bag, or as complex as repurposing an old building into something new (like a bakery!).
Recycling is important because it reduces the need for raw materials, which makes sense since most things are made from other things!
When we recycle aluminium cans in particular, we're also reducing our dependence on fossil fuels--that's because mining uses up lots o' energy and creates waste products like sulfuric acid runoff that pollute water sources.
Reducing the amount of stuff we buy and using what we have longer are also important because they cut down on waste. And when it comes to waste, less is more.