In AC (alternating current) systems, **two main types of transformers** are commonly used:
1. **Step-up Transformer**: This transformer increases the voltage from the primary side to the secondary side. It is often used in power transmission to boost the voltage before it travels over long distances, reducing energy losses.
2. **Step-down Transformer**: This transformer decreases the voltage from the primary side to the secondary side. It is used in applications where a lower voltage is needed, such as in homes and factories for powering electrical devices.
Both types work on the principle of electromagnetic induction, and they are typically used in AC circuits because transformers rely on alternating current to induce voltage changes.
In short:
- **Step-up transformer** increases voltage.
- **Step-down transformer** reduces voltage.
These transformers are used for efficient power distribution and for adapting voltage levels according to the needs of different devices or systems.