FCN

A Fully Convolutional neural network (FCN) is a normal convolutional neural networks(CNN), where the last fully connected layer is substituted by another convolution layer with a large "receptive field". The idea is to capture the global context of the scene (Tell us what we have in the image and also give some very roughe idea of the locations of things).

Reference:
Long, J., Shelhamer, E., & Darrell, T. (2015). Fully convolutional networks for semantic segmentation. In Proceedings of the IEEE conference on computer vision and pattern recognition (pp. 3431-3440).