Signalator provides a number of trading signals for major currency pairs. The trading signal is a unique trading system with its own trading rules, levels of stop loss and take profit, open / close triggers, etc. A currency pair is simply an instrument to trade with. But the way to trade is a trading signal. To distinguish trading signals for a similar currency pair, we use various extensions: XT, Basic, Plus, Pro, etc. So basically, these are completely different trading signals with different trading approaches.
For example, basic signals make about 5 trades a month with about 100 pips TP level, 30 pips SL level and are targeted for big trend movements, whilst XT signals use 75 pips TP levels and 25 pips SL level and make about 20-25 trades a month. So if you see EURUSD signal and EURUSD XT signals, these are two different trading signals which simply are traded for the same currency pair. And the currency pair is the only common for these two signals. Read more here.