How does WiFi actually transmit data through the air?

WiFi transmits data using radio waves, typically at 2.4 GHz or 5 GHz frequencies. Your router converts digital data into radio signals by modulating the waves, meaning it varies properties like amplitude or phase to encode binary information. This technique is called OFDM (Orthogonal Frequency Division Multiplexing), which splits data across many sub-frequencies simultaneously to improve speed and reduce interference. Your device's wireless adapter receives these radio waves through its antenna, which induces tiny electrical currents that are then decoded back into digital data. The process works in both directions at once on modern routers using separate frequency bands or time-division techniques. Walls and obstacles weaken the signal because they absorb or reflect radio energy, which is why distance and obstructions reduce performance.