title: What is the difference between .pt, .pth and .pwf extentions in PyTorch?
body: <p>I have seen in some code examples, that people use .pwf as model file saving format. But in PyTorch documentation .pt and .pth are recommended. I used .pwf and worked fine for small 1->16->16 convolutional network.</p>
  
  <p>My question is what is the difference between these formats? Why is .pwf extension not even recommended in PyTorch documentation and why do people still use it?</p>