The main language spoken here is German. Many people also speak English because they start learning it in school around second grade. However in Liège, Belgium--which is only 2 hours away--they speak French!
Germany uses the Euro (€). Coins are very common, and smaller shops sometimes prefer cash over cards.
There is no free tap water in restaurants in Germany, so you usually have to pay for water. A small bottle typically costs around 2 euros, and sparkling water is very popular.
Not a full meal, but my favorite snack was a Belgian waffle, coated in warm cinnamon syrup and perfectly gooey and delicious.
I mostly listened to American music, but Bonn always has street performers. I saw people playing guitar, saxophone, accordion and many other instruments. The music makes walking through the city feel lively and fun.