As regards the pound sterling symbol: this is allocated Unicode code-point U+00A3.
If you use the ISO8859/1 Latin-1 coded character set (HP symbol set 0N) this provides a simple mapping to the first 256 Unicode characters (those defined in row 0 of plane 0 (the Basic Multilingual Plane (BMP)).
i.e. 0xA3 maps to U+00A3 , etc.
The Windows ANSI coded character set (symbol set 19U) is a 'superset' of ISO 8859/1, in that characters in the range 0x80-0x9F (which are defined in ISO 8859/1, and Unicode, as 'undefined control codes) are used within Windows ANSI to map to various additional characters (with Unicode code-points at or above U+0100).
Most common operating systems in use today (in the western world) default to use of ISO 8859/1 or Windows ANSI (for 8-bit working), although many actually use (16-bit) Unicode internally.
Most browsers support ISO 8859/1, but also support UTF-8, which is a standard mechanism for representing 16-bit Unicode (UCS-2) or 32-bit UCS-4 values unambiguously, whilst allowing for short 8-bit forms for the standard ASCII characters; I don't think that many (if any?) printers support UTF-8.