A symbol, in the language of markets, is better known as a ticker symbol, the entry that explains how these codes are assigned and used across exchanges. This page explains the shorter word, which trading platforms, data feeds and crypto sites use on their own.
A symbol is a short, unique code that identifies a tradable asset so that it can be searched, quoted and ordered quickly. On a stock exchange, a company's shares might be listed under three or four letters. In currency trading, a symbol joins two currency codes to show a currency pair, such as EUR/USD. In crypto, symbols such as BTC for bitcoin or ETH for ether identify coins and tokens, and an exchange often shows a cryptocurrency pair such as BTC/USDT.
The two words mean the same thing in practice. "Ticker" comes from the stock ticker machines that printed prices on paper tape from the nineteenth century onwards, while "symbol" is the more general term used in software. Unlike stock symbols, which exchanges assign, crypto symbols are chosen by token creators and are not unique: several unrelated tokens can share the same symbol, and scammers sometimes copy a well-known one. For that reason, crypto users are advised to check a token's contract address rather than rely on its symbol alone.