C++ keywords, explicit, default, delete, noexcept, override, and final

explicit
prevent use for implicit conversion in side a class

for example

explicit Array(int size);

This code prevent implicit conversion from int to Array class

default
Let compiler generate default functions.

delete
Remove the default implementation of a method

Array(const Array&) = delete;

for example, the above code prevents C++ from automatically creating copy constructor

noexcept
Optimize the code without worrying about exception. Does not guarantee there is no exceptions throw in the function.

override
Tell a virtual function it must override a function in the base class. Preventing override with different parameters.

final
disallow inheritance from class or function
for example

struct Base final{
}

Base struct cannot be inherited.