Identifiers
Ticker Symbol
Short letter code under which a security trades on an exchange.
Ticker symbols are the best-known security identifiers — AAPL for Apple, MSFT for Microsoft, BRK.B for Berkshire Hathaway Class B. They are short, intuitive and ubiquitous in financial news and trading platforms.
However, tickers are not stable: they change on mergers, spin-offs or reorganisations. For clean time-series analysis across multiple quarters the CUSIP is therefore the better key; the ticker is only derived from it for display.