Excitatory and inhibitory synapses or neurons?

[katenkak]

Hi all,
Better stupid question now than staying stupid forever later  . I can't figure out from all the literature I read whether neurons are classified into either excitatory and inhibitory or the same neuron can have both excitatory AND inhibitory synapses? In the first case (either exc. or inh. neuron), does for exc. hippocampal or cerebellar granular neuronal culture contains only one type of neurons or mixture?
Thanks a lot for the answer.