I am following this tutorial and this guy puts in his code m_Entries and doesn't explain it at all at least I think. So any one who has done skeletal animation show me what he is talking about by m_Entries.
The m_Entries member of the Mesh class is a vector of the MeshEntry struct where each structure corresponds to one mesh structure in the aiScene object. That structure contains the vertex buffer, index buffer and the index of the material.
This is the type of answer you could easily have found by yourself by at least skimming earlier parts of the tutorial, or, worst case, downloading the full source from the link above and looking in
mesh.h to see how it's used.