Its main features (many of them unique) over rxvt are:

• Stores text in Unicode (either UCS-2 or UCS-4).
• Uses locale-correct input, output and width: as long as your system supports the locale, rxvt-unicode will display correctly.
• Daemon mode: one daemon can open multiple windows on multiple displays, which improves memory usage and startup time considerably.
• Embedded perl, for endless customization and improvement opportunities, such as:
  • Tabbed terminal support.
  • Regex-driven customisable selection that can properly select shell arguments, urls etc.
  • Selection-transformation and option popup menus.
  • Automatically transforming the selection once made.
  • Incremental scrollback buffer search.
  • Automatic URL-underlining and launching.
  • Remote pastebin, digital clock, block graphics to ascii filter and whatever you like to implement for yourself.
• Crash-free. At least I try, but rxvt-unicode certainly crashes much less often than rxvt and its many forks, and reproducible bugs get fixed immediately.
• Completely flicker-free.
• Re-wraps long lines instead of splitting or cutting them on resizes.
• Full combining character support (unlike xterm :).
• Multiple fonts supported at the same time: No need to choose between nice japanese and ugly latin, or no japanese and nice latin characters :).
• Supports Xft and core fonts in any combination.
• Can easily be embedded into other applications.
• All documentation accessible through manpages.
• Locale-independent XIM support.
• Many small improvements, such as improved and corrected terminfo, improved secondary screen modes, italic and bold font support, tinting and shading.
• Encapsulation of privileged operations in a separate process (improves security).
• Optimised for local and remote connections.

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