#Introduction
#From Linear to Nonlinear
#Understanding Neural Network Architecture
Neural Network Architecture with Notation
#How to Improve Model Accuracy
#Try It Yourself
A
Ayushi Sahu
AI Engineer
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Deep Learning·23rd Nov 2025·4 min read
Forward Propagation Explained: The First Step to Training Neural Networks
In order to understand how to train an LLM, we first need to understand backpropagation. And before we get there, we need to understand the stage where everything begins: forward propagation.
💡TL;DR
- •Multiple perceptrons stacked together form a Multi-Layer Perceptron (MLP).
- •Forward propagation passes data through the network layer by layer.
- •Each layer applies weights, biases, and a nonlinear activation function.
From linear decision boundaries to nonlinear curves using multi-layer perceptrons