MT4 and MT5 are widely used trading platforms developed by MetaQuotes. They offer charting, indicators, and automated trading (via Expert Advisors). While not essential, they provide value through reliability and built-in tools. Traders can program custom solutions, but these platforms save time for those who prefer a ready-made environment.
In my experience, MT5 is the best trading platform I've used so far. While it may not be the most visually appealing or stylish, it excels in being fast, responsive, and stable, with very few bugs (I use the build provided by HFM). Additionally, since offering CFD trading via Metatrader platform is the industry standard, there aren’t many alternatives to choose from.