# What does "Norm" term mean?

In this paper (page 1 abstract) which considers regularization technique, the author used the word "norm" - what does it stand for? Is it related to Batch Normalization / L1 or L2 Normalization?

"We stabilize the activations of Recurrent Neural Networks (RNNs) by penalizing the squared distance between successive hidden states’ norms"

Googling "what is a norm Neural Net" doesn't provide any links

• The state of a neural network is a vector or tensor, and these mathematical objects have norms.
– Emre
Feb 27 '18 at 2:44

In this paper, they are training a recurrent neural network. These are used for time series data. The assumption is a hidden state should be similar for successive time inputs $t$ and $t-1$. Thus, the author proposes an additional constraint based on the relative size of the successive hidden state vectors as
$||h_{t}||_2 - ||h_{t-1}||_2$.