In these lectures I will show some results obtained with the chiral unitary approach applied to the photo and electroproduction of mesons. The results for photoproduction of $eta pi^0 p$ and $K^0 pi^0 Sigma^+$, together with related reactions will be shown, having with common denominator the excitation of the $Delta(1700)$ resonance which is one of those dynamically generated in the chiral unitary approach. Then I will show results obtained for the $e^+ e^- to phi f_0(980)$ reaction which reproduce the bulk of the data except for a pronounced peak, giving support to a new mesonic resonance, X(2175). Results will also be shown for the electromagnetic form factors of the $N^*(1535)$ resonance, also dynamically generated in this approach. Finally, I will show some results on the photoproduction of the $omega$ in nuclei, showing that present experimental results claiming a shift of the $omega$ mass in the medium are tied to a particular choice of background and are not conclusive. One the other hand, the same experimental results show unambiguously a huge increase of the $omega$ width in the nuclear medium.
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