Shamelessly sharing blog post from Colah: http://colah.github.io/posts/2015-08-Understanding-LSTMs/
this is an incredible illustrative post on what LSTM is and how they were proposed. Big shoutout here and I’d recommend every Deep learning beginners to checkout this blog post.
In addition to that, this https://jasdeep06.github.io/posts/Understanding-LSTM-in-Tensorflow-MNIST/ is also a good hands-on tutorial on LSTM in tensorflow. It peeled of the complex NMT stuff that beginners may find intimidating at the first place, and focus on the LSTM implementation first.
Sherman Wong 