A bicycle, also known as a pedal bike or cycle, is typically a two-wheeled vehicle, propelled by pedaling, and serves as an eco-friendly means of transportation.

The word "bicycle" in English originates from "bi" meaning two and "cycle" signifying wheels, representing its dual-wheel structure.

It serves as an eco-friendly mode of transportation for commuting and travel, increasingly utilized for fitness through cycling exercises and bike touring. Furthermore, cycling encompasses various competitive sports such as road cycling, mountain biking, track cycling, and BMX competitions.

In the late 18th century (1790), the Comte de Sivrac from France produced the world's first bicycle. Termed as a "wooden horse," it featured two wheels connected by a wooden beam where the rider sat and propelled forward by pushing feet against the ground. While lacking a driving or steering mechanism, it captivated onlookers when Sivrac rode it in the park. However, his intention to refine the "wooden horse" was interrupted by his demise.

In 1818, German inventor Karl Drais created an improved wooden two-wheeled bicycle with a handlebar, patented in Germany and France. Although still relying on foot pedaling, it allowed directional changes while in motion, garnering significant interest and mass replication, becoming the first practical bicycle.

In 1839, British inventor Macmillan refined Drais' "hobby horse," creating a pedal-driven bicycle. He added cranks to the front wheel's axle, connecting them to pedals, replacing wooden wheels with iron ones, and implementing solid rubber tires. With this iteration, both feet no longer touched the ground, enhancing the cycling speed.

1867 saw further enhancements by the Michaux family in France, adding rotating pedals on the front wheel, leading to the bike being labeled as the "bicycle." Displayed at the Paris Expo, this upgraded bicycle sparked immense public interest, igniting a bicycle craze.

In 1888, Irish veterinarian Dunlop, inspired by his experience treating inflated cow stomachs, invented the pneumatic tire by sealing rubber tubing and pumping air into it, marking the beginning of inflatable tires. This innovation fundamentally altered cycling performance, resolving the longstanding discomfort of vibrations, and significantly boosting cycling speeds, enhancing its functionality.

From 1791 to 1888, nearly a century of relentless efforts and improvements by these inventors revolutionized bicycles. It became a transformative technology akin to today's smartphones. An affordable, speedy, and fashionable means of transportation, the bicycle emerged as a must-have for travel, similar to how smartphones are indispensable today.

The bicycle, easy to learn and use, became accessible to people and embraced worldwide. Today, the bicycle remains the most used, simplest, and most practical mode of transportation globally.