This is Hagia Sophia and it first was a Orthodox patriarchal basilica (really big church) later an imperial church and now a museum.
This is a Simit. It's a traditional turkish snack, you can basically find everywhere in the city, just like hot dogs in New York. It baked bread with burned sesame on it, like a kind of pretzel.
This is the Mausoleum of Mustafa Kemal Atatürk. A mausoleum is basically the grave of someone important. Indeed Mustafa was a really important army officer. This is situated in Ankara, a really important city in turkey.
This is an ottoman janissary. He is the ottoman's elite. There are 30 000 of them in total and they can be of any religion or race when recruited, but then they have to turn muslim if they aren't. They are skilled in almost every war practice, they are the sultan's elite.
It's one of the best foods in Istanbul, the Kumpir. You take a loaf of old and dry bread and you remove the crumb, then you can put whatever you want, what I prefer to put more is some chicken, salad, tomatoes, tuna, capers, eggplant and cheese.
This is Goke, an ottoman war ship. I couldn't take a picture of it because the janissaries were around so I just drew it. They used this ship to attack Adrianopole (in rhodes). After this the ottoman empire got the control of all the middle east.