recipes-connectivity - Libraries and applications related to communication with other devices 
recipes-core         - What's needed to build a basic working Linux image including commonly used dependencies
recipes-devtools     - Tools primarily used by the build system (but can also be used on targets)
recipes-extended     - Applications which whilst not essential add features compared to the alternatives in
                       core. May be needed for full tool functionality or LSB compliance.
recipes-kernel       - The kernel and generic applications/libraries with strong kernel dependencies
recipes-phosphor     - Phosphor OpenBMC applications and configuration
recipes-protocols    - bbappends from recipes-protocols in the meta-networking layer