Transformers

Transformers revolutionized NLP and are now used across AI. They process entire sequences in parallel using self-attention, unlike RNNs which process sequentially.

Key Innovation: "Attention is All You Need" (2017) - Transformers replaced recurrence with attention mechanisms.

Architecture Components

Encoder

Processes input sequence and creates contextual representations using self-attention and feedforward layers.

Decoder

Generates output sequence using encoder outputs, self-attention, and cross-attention mechanisms.

Positional Encoding

Since Transformers don't have inherent sequence order, positional encodings are added to give the model information about token positions.

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Output:
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Why Transformers Dominate

  • Parallelization: Process entire sequences at once (faster training)
  • Long-range Dependencies: Attention can connect any two positions
  • Scalability: Performance improves with more data and parameters
  • Versatility: Used in GPT, BERT, Vision Transformers, and more