# Index

Canonical page: https://synoptiv.com/glossary/index

A rules-based basket that measures a slice of the market.

Also known as: Indices, Indexes, Stock index, Market index

## Definition

A market index tracks the value of a defined group of securities, such as the S&P 500 or Nasdaq-100. Indexes are benchmarks; investors usually gain exposure to them through funds that track them.

## Related terms

- [52-week high](https://synoptiv.com/glossary/52-week-high)
- [52-week low](https://synoptiv.com/glossary/52-week-low)
- [AI-written analysis](https://synoptiv.com/glossary/ai-analysis)
- [Analysis as-of price](https://synoptiv.com/glossary/analysis-as-of-price)
- [Analysis version](https://synoptiv.com/glossary/analysis-version)
- [Analyst consensus](https://synoptiv.com/glossary/analyst-consensus)
- [ATR](https://synoptiv.com/glossary/atr)
- [Attention](https://synoptiv.com/glossary/attention)

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