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+/**
+ * \page thread-safety Reentrancy and Thread-Safety
+ *
+ * Through the documentation, several terms are used to define how classes and
+ * their member functions can be used from multiple threads.
+ *
+ * - A **reentrant** function may be called simultaneously from multiple
+ *   threads if and only if each invocation uses a different instance of the
+ *   class. This is the default for all member functions not explictly marked
+ *   otherwise.
+ *
+ * - \anchor thread-safe A **thread-safe** function may be called
+ *   simultaneously from multiple threads on the same instance of a class. A
+ *   thread-safe function is thus reentrant. Thread-safe functions may also be
+ *   called simultaneously with any other reentrant function of the same class
+ *   on the same instance.
+ *
+ * \internal
+ * - \anchor thread-bound A **thread-bound** function may be called only from
+ *   the thread that the class instances lives in (see section \ref
+ *   thread-objects). For instances of classes that do not derive from the
+ *   Object class, this is the thread in which the instance was created. A
+ *   thread-bound function is not thread-safe, and may or may not be reentrant.
+ * \endinternal
+ *
+ * Neither reentrancy nor thread-safety, in this context, mean that a function
+ * may be called simultaneously from the same thread, for instance from a
+ * callback invoked by the function. This may deadlock and isn't allowed unless
+ * separately documented.
+ *
+ * \if internal
+ * A class is defined as reentrant, thread-safe or thread-bound if all its
+ * member functions are reentrant, thread-safe or thread-bound respectively.
+ * \else
+ * A class is defined as reentrant or thread-safe if all its member functions
+ * are reentrant or thread-safe respectively.
+ * \endif
+ * Some member functions may additionally be documented as having additional
+ * thread-related attributes.
+ *
+ * Most classes are reentrant but not thread-safe, as making them fully
+ * thread-safe would incur locking costs considered prohibitive for the
+ * expected use cases.
+ */