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Background Field Method (BFM) and Pinch Technique (PT) are two methods to maintain explicity gauge invariance when quantization is done in a field theory. BFM is a quantum field theory and it works at all levels in perturbation theory. BFM can be applied to every interaction vertex and Green function too. The PT has the same goal BFM but it is not a quantum field theory so it has to construct the variables and functions in the way they would be gauge invariant. The article's aim is to compare these methods and to show sorne applications from them.