Most alphabets in the world grew slowly, over hundreds or thousands of years, with no one knowing exactly when or how they started. The Armenian alphabet is unusual because we know exactly when it appeared and who made it. Mesrop Mashtots designed 36 letters in the year 405, so that the Armenian language could finally be written down.
Before then, Armenians had been speaking their language for centuries, but they had to use other people's alphabets - Greek, Syriac, or Persian - to write it. None of those alphabets fitted Armenian sounds well. Mashtots designed his letters carefully so that every Armenian sound had exactly one letter.
Two more letters were added a long time later, so the modern Armenian alphabet has 38 letters - 8 more than English. The letters look completely different from English ones: ա բ գ դ ե… Some have curves like little dancers, others have hooks like fish.
On a hillside in Armenia you can visit a special monument called the Armenian Alphabet Park, where each of the 39 stone letters has been carved as tall as a person and placed in a giant outdoor sculpture. School groups visit on field trips and try to spot the letters of their own names.