Above, you could see all the denominations of Turkish Lira both in paper money & coins. Here is a small explanation for the travelers who visit Turkey very first time.
1 Krs : Practically no use, there is a very small chance for you to see it under circulation because of its extremely low value
5 Krs : The smallest currency in use, still have a very very low value. Supermarkets, and in public transportation could pass it to you for a change.
10 Krs : Same with 5 krs, another small currency in use, still have a very very low value. Supermarkets, and in public transportation could pass it to you for a change.
25 Krs : Well, at least four of them together create a value 🙂 For 25 Krs, you could buy a single chewing gum in a discount store or possibly one box of matches.
50 Krs : Smallest amount good for vending machines. Single one could buy you a nice gum which guarantees you a big balloon. You could get some local brand snacks for 50 krs in discount stores.
1 TL : The highest value of Turkish coins. Good for vending machines such as trolley at the airport, basic snacks in vending machines. If you are up early in the morning it could get you a nice “pogaca” a Turkish breakfast salted pastry.
Paper Money :
5 TL : The smallest paper denomination in circulation. Good for quick snacks, public transportation as well as ferry tokens. As of mid 2015, you could get a single cheapest burger in Mc Donald for little less than 5 TL. Also good for local can/bottle beers as well as non alcoholic beverages from supermarkets.
10 TL : Good for having coffee, starbucks take outs, and some local beer in low budget pubs.
20 TL : It could get you a decent lunch. Also good for taxi trips in short-mid distances.
50 TL : Good for a nice lunch as well as 2 person dinner in low budget restaurant.
100 TL : Well, it is the second highest denomination and you could have difficulty to get chances when you are purchasing 5 to 10 tl goods. You can buy a pair of local brand shoes as well as single item clothes such as t-shirts, jeans, etc.
200 TL : Always be careful about counter fraud. Highest denomination and mostly salesmen on the street would give you hard time to accept or provide you some chance.