What does BERT stand for and what is it trained to do?
PICTURE THIS: A SENTENCE BECOMES TOKENS
The model does not read letters like humans. It reads these pieces, then predicts the next one.
Simple meaning
BERT stands for Bidirectional Encoder Representations from Transformers.
WHY — Tokens instead of words?
LLMs use tokens (not full words) because it helps them:
separate people who only read docs from people who shipped.
and tied to GenAI / LLM work.
Each piece maps to a number the network can learn.
Fixed pieces are what transformers expect as input.
STEPS — What happens with tokens?
Before the model can read a sentence, it goes through these steps:
- 1BERT stands for Bidirectional
Encoder Representations from Transformers.
- 2It is trained with
masked language modeling, filling in hidden tokens using left and right context.
- 3That makes it strong
for classification, NER, and sentence embeddings, not free-form generation.
- 4Context mix
Attention looks at nearby tokens together.
- 5Next token
The model scores what should come next.
- 6Decode
IDs turn back into readable text.
EXAMPLE — See it in action
Let's see how a real sentence is tokenized (tokens may vary by model):
Note: Actual tokens and IDs depend on the tokenizer (e.g., GPT, Llama, etc.).
Key takeaway
BERT stands for Bidirectional Encoder Representations from Transformers. It is trained with masked language modeling, filling in hidden tokens using left and right context.