Binary and hexadecimal numbers systems underpin the way modern computer systems work. Low-level interactions with hexadecimal (hex) and binary are uncommon in the world of Java programming, but ...

According to the XML 1.0 specification, valid character values include the following ranges of hexadecimal values: 0x9, 0xA, 0xD, 0x20-0xd7ff, 0xe000-0xfffd, and 0x10000-0x10ffff.