Key WiFi modules for embedded systems include ESP8266, ESP32, and TI CC3200. The ESP8266 is popular due to its low cost, robust features, and ease of integration. It supports 802.11 b/g/n and has a built-in TCP/IP stack, making it ideal for IoT applications. The ESP32, an upgrade to the ESP8266, adds dual-core processing, Bluetooth support, and enhanced security features. It's widely used in smart devices and wearables due to its versatility and power efficiency.

The TI CC3200 stands out with its unique SimpleLink WiFi technology, which simplifies the development process by providing a single-chip solution. It offers high performance, integrated security, and extensive development tools, making it suitable for complex embedded applications. Other notable modules include the Qualcomm QCA4002/4004, which provides advanced connectivity options and robust security, and the Marvell 88W8977, known for its low power consumption and multi-protocol support.

Selecting the right WiFi module depends on factors like power requirements, processing needs, and security considerations. These modules have made it easier for developers to integrate WiFi connectivity into their projects, enhancing functionality and user experience. For those looking to deepen their knowledge and skills, an embedded system certification course can provide comprehensive training in using these modules effectively.