Leading Indicators are based on such a mechanism that obtains past price data in order to predict upcoming price movements, hence, therefore, such indicators enable traders to analyze/predict/have an idea of future price movements. The commonly know RSI (Relative Strength Index) Indicator is a genuine example of a Leading Indicator.

Whereas a Lagging Indicator runs on such mechanism which is in action behind the price movements also it gives feedback lately to traders.
The Moving Average Indicator is a crystal clear example of a Lagging Indicator. Such indicators are helpful in a sense because they have the ability to simplify Price Action & show traders where the price has been.

A leading indicator is a measure of economic activity that predicts upcoming changes in the economy, such as an upturn or downturn. A lagging indicator is a measure of economic activity that mostly illustrates what has already happened in the economy, such as GDP. The Fed will use both types of indicators to help them determine where the economy is going and how they should react with monetary policy.

A leading indicator is any economic statistic that provides information about the future state of the economy. Examples include changes in oil prices, stock markets, and unemployment rates. A lagging indicator provides information about the present state of the economy, such as changes in GDP over a certain period of time or number of jobs created in a specific year. Lagging indicators are more informative than leading indicators because they tell us what has happened and not what is going to happen.

Both are important indicators. The leading indicator shows what is going t lead the economy in the future, whilet the lagging indicator offers some insight on the current state of the economy. The latter tend to be more informative as they are shedding light on current situations as well as offer some overview of the near future.