A caret (^) indicates an addition, and a line through the text indicates a deletion or a replacement. A mark is also placed in the text to indicate where the correction needs to be made. In hard copy proofreading, corrections typically appear in the left or right margins beside the line containing the error.
The proofreader uses a series of symbols and abbreviations to suggest changes, correct spelling errors, improve punctuation, and generally enhance the quality and readability of a hard copy document. These strange markings are the 'footprint' that your proofreader has left on the document to highlight where changes need to be made to the text. Your returned document is so full of symbols (hieroglyphics? squiggles? cuneiform script?!) that you think it has been translated into Martian!
If you've ever had a hard copy of a document proofread, chances are that you're familiar with the strange typology of professional proofreaders.
