Special types of substances used to test whether a substance is acidic or basic are called indicators .
Some indicators are found naturally in the environment, and some are synthetically made (by man).
What are Natural Indicators?
The indicators that are derived from natural sources like plants are known as natural indicators.
For Example - Turmeric , Litmus , China Rose petals(Gudhal)
What are Synthetic Indicators?
Man-made indicators are known as synthetic indicators.
For Example - Phenolphthalein
