UTF-8 bomb is also called UTF-8 signature. In fact, UTF-8 BOM has no effect on UFT-8, but it was added to support UTF- 16 and UTF-32. The meaning of BOM, BOM signature is to tell the editor what coding is used in the current document, which is convenient for editing and identification. However, although the BOM is not displayed in the editor, it will produce output, just like an extra blank line.