A trading journal is an ongoing record of every trade taken — entry and exit price, size, reasoning, and outcome — kept specifically to review performance and spot patterns over time. It turns vague impressions ("I feel like I lose more on Fridays") into checkable facts, and it's the raw data behind metrics like win rate, profit factor, and expectancy.
Many traders extend the journal beyond the numbers to include the emotional state and reasoning behind each trade, since patterns in decision-making are often as revealing as the P/L itself.
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Guide
Choosing a Trading Platform: MT4, MT5, cTrader and the Broker's Own
The platform decides which orders you can place, whether your stops survive a closed laptop, and how much you would have to rewrite to leave. What actually differs between the options — and the point where the platform stops mattering and the broker takes over.