What is an RNN (recurrent neural network)?

A recurrent neural network, or RNN for short, is an artificial neural network-based Machine Learning technique. RNNs are used to discover patterns in a series of data, such as time series, stock market data, temperature data, and so on. RNNs are a type of feedforward network in which data from one layer is sent to the next and each node conducts mathematical operations on the input. RNNs hold contextual information about earlier calculations in the network, therefore these operations are temporal. It’s named recurrent because it repeats operations on the same data each time it’s passed.
However, depending on previous computations and their outcomes, the output might be different.