IoT Exam Review – Key Vocabulary

Vocabulary flashcards covering essential IoT, microcontroller, networking, and database terms for the upcoming exam.

Sensor

Device that detects physical phenomena and converts them into digital data for an IoT system.

Actuator

Output device that performs a physical action (e.g., open a valve, turn on a motor) based on received data.

Connectivity

Network link that transports data from edge devices to processing resources; examples include Wi-Fi, Bluetooth, 4G/5G.

Data Processing

Stage where raw sensor data are filtered, analyzed, and turned into actionable information, either in the cloud or at the edge.

Interface (User Interface)

Visible layer—such as mobile apps or web dashboards—through which users monitor data and control IoT devices.

Edge Computing

Local data processing close to the data source, enabling low-latency responses and reduced bandwidth usage.

Cloud Computing

Centralized, scalable processing and storage of IoT data in remote data centers.

Microcontroller

Self-contained computer on a chip with CPU, memory, and I/O ports that controls sensors and actuators.

Digital Input

Microcontroller pin that reads two logic levels (0/1) from devices such as buttons or motion sensors.

Analog Input

Microcontroller pin that reads varying voltages from sensors; requires an ADC to digitize the signal.

ADC (Analog-to-Digital Converter)

Circuit that converts analog signals into digital values a processor can use.

Arduino IDE

Development environment used to write, compile, and upload C/C++ sketches to boards like Arduino Uno or ESP8266.

Arduino Uno

Popular, beginner-friendly 8-bit microcontroller board based on the ATmega328P.

ESP8266

Low-cost Wi-Fi-enabled microcontroller commonly used for IoT networking tasks.

Industrial Internet of Things (I-IoT)

Integration of sensors, machines, and analytics within industrial environments for optimization and automation.

OPC-UA

Platform-independent industrial protocol that securely exchanges data between devices such as PLCs and SCADA systems.

I-IoT Gateway

Bridge device that converts industrial protocols (e.g., OPC-UA) to internet protocols (e.g., MQTT) for cloud integration.

MQTT

Lightweight publish/subscribe messaging protocol optimized for low-bandwidth or unreliable networks.

Publish/Subscribe Model

Communication pattern where clients publish messages to topics and other clients subscribe to receive them.

Topic (MQTT)

Hierarchical string that labels MQTT messages; clients use it to publish or subscribe to data streams.

Single-Level Wildcard (+)

MQTT wildcard that matches exactly one level in a topic hierarchy.

Multi-Level Wildcard (#)

MQTT wildcard that matches all remaining levels in a topic hierarchy.

Measurement Chain

Path from sensor through A/D conversion to data processing in an I-IoT system.

Actuator Chain

Sequence from processed digital command through D/A conversion to physical action by an actuator.

A/D Conversion

Transformation of an analog sensor signal into a digital value for processing.

D/A Conversion

Transformation of a digital control value into an analog signal to drive an actuator.

PLC (Programmable Logic Controller)

Rugged industrial computer designed for reliable, real-time control of machinery and processes.

ISO-OSI Model

Seven-layer framework (Physical to Application) describing standardized network communication.

Edge Device / Gateway

Local computing unit (e.g., Raspberry Pi, industrial PC) that aggregates and processes sensor data near the source.

Compiler

Tool that translates an entire program into machine code before execution, yielding fast runtime speed.

Interpreter

Program that executes code line-by-line without prior compilation; simplifies debugging but may run slower.

Interactive Mode (Python)

REPL environment where Python commands are executed immediately, useful for quick tests.

Script Mode (Python)

Execution of a saved .py file containing multiple lines of code as a complete program.

TCP/IP Stack

Layered suite of protocols (Application, Transport, Internet, Network Access) enabling internet communication.

IP Address

Numeric identifier that uniquely locates a device on a TCP/IP network.

DHCP

Protocol that automatically assigns dynamic IP addresses to devices on a network.

Static IP

Manually configured, unchanging IP address assigned to a device for consistent network access.

setup() Function

Arduino routine that runs once at startup to initialize hardware, networking, or variables.

loop() Function

Arduino routine that repeats continuously, containing the main logic for sensor reading and actuator control.

PubSubClient

Popular Arduino library used on ESP8266/ESP32 to implement MQTT communication.

Client-Server Model

Architecture where clients request services or data from a centralized server, common in database systems.

SQL (Structured Query Language)

Standard language for querying, inserting, updating, and managing data in relational databases.

DQL (Data Query Language)

Subset of SQL focused on data retrieval commands such as SELECT.

DML (Data Manipulation Language)

Subset of SQL used to INSERT, UPDATE, or DELETE records in a database.

DDL (Data Definition Language)

Subset of SQL used to create or modify database schemas, e.g., CREATE TABLE.

Time Series Data

Chronologically ordered measurements, typical in IoT sensor logs, often stored in databases like InfluxDB.