First of all, almost all cafes are restaurants, and the difference between the two is usually in the type of service they provide. A restaurant serves meals and is usually licensed. Restaurants also serve coffee, but generally only regular coffee, although this is changing rapidly.
The restaurant usually serves a wide variety of dishes, including starters, main courses, salads, soups and desserts. While the waiters wait for each dish, all the meals are brought to the table by the waiters. The main restaurant seating area is inside the property, but now most restaurants have an open area for smokers.
Sometimes called cafes and a wide selection of coffee and tea is available, almost all cafes have a suitable espresso machine that can even make cappuccino. The cafe traditionally serves light snacks and simple dishes, perhaps with a wide range of pastries and cakes. Many customers line up at the counter for pre-made coffee or breakfast. The cafe has recently expanded its food options and has become an informal restaurant with a small, minimal menu. Cafes often have an outdoor setting, such as the famous Paris Street Cafe, where patrons drink coffee and read the newspaper or see the world.
The big difference between a cafe and a restaurant is the price, usually you only order snacks and coffee so the cafe is usually very cheap. However, the restaurant serves a wide variety of food, from fast food types to five star restaurants. The tip for service in the restaurant should be much higher than in the cafe, often in a regular cafe you will drop small coins instead of your coffee, but the tip for the service in the restaurant is mandatory and the total bill.
However, it is important to note that the service and food quality in many cafes is better and cheaper than in some restaurants. The terms restaurant and cafe are probably a bit vague to describe the two types of business, the decision-making choice is yours and you call it what you want it to be.