I am trying to understand yocto terminology. I understood that recipe is a set of instructions used by bitbake tool to fetch the source code, configure, compile and generate the package ( software component ).
Metadata is collection of Configuration files ( .conf ), Recipes ( .bb and .bbappend ) , Classes ( .bbclass ) and Includes ( .inc ).
What I don't understand is the term 'layer'. Is the term 'layer' and 'metadata' both same or different
For example: meta-fsl-arm : Is this a layer or metadata.
Metadata is just a generic term for data describing other data as wiki explains.
Layers are recipe containers (folders), so meta-fsl-arm is indeed a layer.
I suggest you to read some documentation, those slides helped me, as well as mega manual and Yocto wiki.