Final answer:
The function of the format painter is to copy formatting from one part of a document to another. It applies the same styling from the source to the target without changing the actual text content.
Step-by-step explanation:
The function of a format painter is to copy formatting from one part of a document to another. It does not change the font per se or increase the font size; rather, it applies the same styling (font type, size, color, text effects, etc.) from the selected source to the target location. For example, if you have formatted a piece of text with bold, italicized Arial font at size 12, and you want another section of text to have the exact same formatting, you would use the format painter to apply these styles directly to the new section without having to manually set each formatting option.