Python is often recommended for beginners in IoT development due to its simplicity, readability, and extensive libraries like MicroPython and CircuitPython designed for microcontrollers. Klingon, Brainfuck, and Assembly are not suitable for beginners due to their complexity and lack of IoT-specific libraries.

In the realm of IoT, M2M (Machine-to-Machine) communication is when devices autonomously communicate with each other without human intervention. This kind of communication is at the heart of the IoT concept, where devices exchange data and instructions seamlessly.

A smart city using sensors to manage traffic in real-time is an example of M2M (Machine-to-Machine) communication. In this scenario, sensors and machines (traffic management systems) communicate with each other to optimize traffic flow and enhance overall city efficiency without direct human involvement.

Devices that have a predefined lifespan after which they should be decommissioned to ensure network security are following the "End-of-Life" principle. This means that after a certain period, these devices are no longer supported and should be replaced or upgraded to maintain security. This is crucial in preventing vulnerabilities that may arise from outdated or unsupported hardware.

The storage requirements for IoT data are typically enormous and scalable. IoT devices generate a continuous stream of data, and this data must be stored for analysis and decision-making. As the number of IoT devices and data volume grow, the storage infrastructure must be able to expand to accommodate the increasing data demands.

Edge computing is the type of computing that processes data closer to the data source in IoT. It's designed to reduce latency and enhance real-time data processing by moving computations closer to where the data is generated.

IoT devices often generate diverse data types, including structured, semi-structured, and unstructured data. NoSQL databases are a suitable choice because they can handle various data types, provide flexibility, and scale horizontally to accommodate the growing data from wearable devices.

Requiring both a password and a biometric scan is a form of Two-Factor Authentication (2FA). It adds an extra layer of security beyond a simple password, making it harder for unauthorized users to gain access.

The integration of 5G technology in IoT can substantially improve interoperability, ensuring that various IoT devices can communicate effectively and efficiently. This is a challenge that 5G addresses in the IoT landscape.

C++ is often considered the most suitable language for real-time IoT applications due to its efficiency and low-level control over hardware. It allows for precise resource management, which is crucial for real-time systems. While Python, Java, and Ruby have their merits, they may not be as well-suited for real-time IoT.