Why does smoke does not go straight up in air?

Smoke doesn't always go straight up due to factors like air currents, temperature gradients, and surrounding obstacles. When smoke rises, it can encounter varying air densities and wind patterns that cause it to drift sideways or swirl. Additionally, the presence of cooler air can create downdrafts, causing the smoke to disperse rather than ascend directly. These dynamics result in a more complex movement of smoke in the environment.