HardJava
Java Quiz: advanced memory, threads and modern API
Test your advanced Java knowledge: heap and stack, garbage collector, immutable String, threads, synchronized, volatile, ExecutorService, Optional and records.
World quizzes
World geography, oceans, continents
From the Pacific to the Atlantic, from Antarctica to the Sahara, this World theme takes players around the globe to explore the planet as a whole. It covers the oceans, the continents, the great deserts and forests, islands, straits and the canals that shape navigation, such as Gibraltar, Suez or Panama, as well as climates and the key reference lines of the Earth: the equator, the tropics and the polar circles.
You compare distant regions, from the Indonesian archipelago to the fjords of Patagonia, and learn where the major natural and human landmarks of the world lie. The quizzes are free, with five levels running from very easy to expert and a detailed explanation after each answer, so you understand the map rather than simply recite it.
Quizzes
MediumJava
Java Quiz: OOP, inheritance, interfaces and collections
Test your object-oriented programming knowledge in Java: inheritance, interfaces, encapsulation, static, exceptions, collections, generics and equals.
EasyJava
Java Quiz: language basics, types and syntax
Test your Java basics: its creator, the JVM, the JDK and the JRE, the boolean and char types, String, arrays, the main method and class names.
Related themes
Frequently asked questions about World
How many continents are there?
It depends on the convention. The seven-continent model (Africa, North America, South America, Antarctica, Asia, Europe, Oceania) is widely used; some countries count six continents by grouping the Americas together, and the Olympic rings symbolise five.
What is the largest ocean in the world?
The Pacific Ocean is the largest and the deepest. It covers close to a third of the Earth's surface on its own and contains the Mariana Trench, whose deepest known point reaches about 11,000 metres below sea level.
What is the largest desert in the world?
It depends on the definition. The Sahara, at about 9 million square kilometres, is the largest hot desert. But a desert is defined by low precipitation, not heat: Antarctica, a polar desert, is larger still at more than 14 million square kilometres.