It's always good to know when Ramadan is when you're visiting Islamic countries (Middle East, North Africa, Central Asia, and some Southeast Asian countries).
For visitors, there are two rules to observe to be polite:
Do not eat or drink in public during the day (no smoking either). Muslims fast from sunrise until sunset, and it's in extremely poor taste to be eating in front of them while they fast. While non-Muslims are not forbidden from eating, do it in private. I've tourists being yelled at for doing so in Cairo
Dress extra modestly. It's a general good practice to dress modestly when visiting Islamic countries, and this is especially so during Ramadan. Avoid wearing sleeveless shirts or singlets, short shorts/skirt, flip flops
These are the Ramadan dates for the next 10 years: