Introduction:
Woollen clothes are made from wool fibers, which are obtained from the fleece of animals like sheep, goats, and rabbits. These clothes are known for their warmth and insulation properties, making them suitable for cold weather conditions.

Explanation:
Woollen clothes primarily help in keeping us warm and comfortable during cold weather. Let's understand how they achieve this:

1. Insulation:
- Wool fibers have a unique structure with natural crimps and overlapping scales, creating air pockets within the fabric.
- These air pockets trap warm air close to the body, acting as insulation and preventing heat loss.
- The trapped air also resists the cold air from outside to enter, maintaining a warm microclimate around the body.

2. Moisture-wicking properties:
- Wool has excellent moisture-wicking properties, meaning it can absorb and release moisture from the body.
- When we sweat, the moisture is absorbed by the wool fibers, keeping the skin dry and preventing the chilling effect caused by wet clothes.

3. Retains warmth even when wet:
- Unlike other fabrics, wool retains its insulating properties even when it gets wet.
- The structure of wool fibers allows them to absorb moisture without feeling damp, and the trapped air pockets continue to provide insulation.

4. Breathability:
- Wool is a breathable fabric that allows air to circulate, preventing overheating.
- It helps regulate body temperature by absorbing excess heat and moisture from the body and releasing it into the environment.

5. Soft and comfortable:
- Woollen clothes are often soft and comfortable to wear due to the natural fibers' texture.
- They provide a cozy and snug feeling, which enhances the overall warmth and comfort.

Conclusion:
In conclusion, woollen clothes keep us warm by providing insulation, moisture-wicking properties, and retaining warmth even when wet. They are breathable, soft, and comfortable, making them an ideal choice for cold weather conditions.