To add a bit, an amino acid can and will protonate itself. So the COOH (carboxylic acid) group “loses” its hydrogen as an ion (called a proton by chemists because that’s what it is). This results in the pronation of the amine (NH2) group. So you’ve got COO- on one end and NH3+ on the other. This is the “zwitterion” form.

Lots of chemistry is learning the vocabulary because the vocabulary makes it easier to communicate quickly.