Market structure is the pattern of highs and lows that price leaves behind as it moves. Reading it means tracking whether the market is making higher highs and higher lows, lower highs and lower lows, or neither. It is a simple framework for describing trend and noticing when that trend may be shifting.
Market structure gives a shared language for trend, which underpins a lot of chart reading and strategy work.
The app files could not be fetched. This is usually a network hiccup or an out-of-date cached copy of the site.