Contaminations of paper that are classified as tacky are also called stickies. The main sources for stickies are recycled paper, waxes, and soft adhesives. Temperature control is important as this affects the stickiness of stickies. Macro stickies are those which are retained as screening residue. The contaminants are mostly printing ink and stickies. A number of applications have duplicated the functionality of Stickies on other platforms. The aggregates are written in yellow stickies. Stickies are an indefinite mixture of organic compounds, with the main part being different esters.