Booleans store logic, not just numbers

A bool stores exactly one of two logical values

The bool type holds one of exactly two logical values: true or false. In the concert-entry example, hasTicket and hasAdultPermission are both bool variables because each answer is either yes or no. The word true in the code is a bool literal. It is not text containing the characters t, r, u, e, and it is not the integer 1, even though C++ can display a true bool as 1.

bool hasTicket = true;
bool hasAdultPermission = true;

The quotes change the meaning completely. A value written as "true" is text, while true without quotes is a bool literal. The integer 1 is also a different value with a different type. Choose bool when the value represents a yes-or-no fact, so the type records what the value means as well as what value it holds.

A comparison produces a bool that you can store

A comparison is an expression with a value, and that value is a bool. Here age is 16 and adultAge is 18, so age >= adultAge asks whether 16 is at least 18. The answer is false. You can store that answer in isAdult, just as you store any other value in a variable.

int age = 16;
int adultAge = 18;
bool isAdult = age >= adultAge;

After the assignment, isAdult contains false. The comparison has not merely performed a test and disappeared. It has produced a reusable bool value that another expression can read later. This lets you give a name to a fact, such as whether the visitor is an adult, before combining that fact with other facts.

Logical operators combine existing bool values into a new bool

Logical operators take bool values and produce another bool value. First evaluate the parentheses in hasTicket && (isAdult || hasAdultPermission). With isAdult equal to false and hasAdultPermission equal to true, the OR expression becomes false || true, which produces true. Then hasTicket is combined with that result. Since hasTicket is true, the final AND expression is true && true, which produces true.

bool entryApproved = hasTicket && (isAdult || hasAdultPermission);

The parentheses show the intended intermediate value directly. The visitor is not an adult, but has adult permission, so the parenthesized expression is true. The visitor also has a ticket, so entryApproved becomes true. Every stage still has a bool result that can be stored or consumed by the next operator.

bool entryApproved = hasTicket && (isAdult || hasAdultPermission);

Printing 1 or 0 does not change a bool into an int

C++ uses 1 and 0 as the default output forms for true and false. Therefore printing entryApproved normally displays 1 for this example. That output is only a presentation choice. entryApproved still has type bool and still stores the logical value true. A printed 1 does not prove that the variable is an int.

cout << entryApproved << '\n';
cout << boolalpha << entryApproved << '\n';

The stream manipulator boolalpha changes how bool values are displayed, not how they are stored. The first line prints 1 using the default form. After boolalpha is enabled, the second line prints true. Both lines read the same bool variable, so storage, type, logical value, and presentation remain separate ideas.