Encre is a kind of solution that is attained form various kinds of setting solutions and the colored backgrounds from various kinds of substances like,
- Organic substances
- Minerals
- Solvents
- Chemicals, and even
- Vegetables.
There are other solutions in encre that are invisible or colorless. When people need to share some secrets or highly confidential information, they will make use of these colorless liquids. The other people who know that the information has been conveyed through invisible encre, they can heat the substance and find out the content or they can make use of other chemicals that will make these inks become visible.