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Types and Value Categories
The type system is one of the most fundamental pieces of C++'s design — it determines how data is laid out in memory, what the compiler checks on your behalf, and what operations you can perform on a given piece of data. In this chapter we start from the basic data types and work out what integers, floating-point numbers, characters, and booleans in C++ really are; then we talk through the trap-ridden implicit rules of type conversion and catch up with our old friend const. Finally, we get a first taste of the idea of "value categories," laying the groundwork for understanding move semantics later on.