This thread is for the site lexicon, you can post if you think that it's on topic but it's not created for a big discussion.
What is l? L is short for litre and a way to measure volume.
1 l is
In other measuring systems 1 l is
4,23 US cups
or 1 l is
or 66,67 tablespoons
If I have missed something (I use metrics so I don't know them all) there is a converter here.