Input may be:

Input
Type here
Input was:U+00b5
 ...interpreting as U+00 style format (hex codepoint, two to eight digits)
Character:         µ         (U+00B5)
Character image
(experiment)
Characters near thisBefore:
¥ ¦ § ◌¨ © ª « ¬ ◌­ ® ◌¯ ° ± ² ³ ◌´
After:
· ◌¸ ¹ º » ¼ ½ ¾ ¿ À Á Â Ã Ä
Note: unprintable, nonspacing and combining characters are shown as or beside 
 
Some unicode data
Character nameMICRO SIGN
Case changeGREEK CAPITAL LETTER MU (U+039C)
CategoriesLeft-to-Right, lowercase letter
Links elsewhere:fileformat.info/info/unicode/char/00b5
codepoints.net/U+00b5
Unicode blockLatin-1 Supplement, U+0080 to U+00FF
(see also the according PDF on unicode.org)
Normalization Original: 00B5 (µ)

NFC (canonical compose):
  no change

NFKC (fuzzy (re-)compose): 03BC (μ)

  Individual characters are:
   GREEK SMALL LETTER MU


NFD (canonical decompose):
  no change

NFKD (~= fuzzy decompose): 03BC (μ)
  Individual characters are:
   GREEK SMALL LETTER MU
 
Font info (experiment)
 
Encoding
Character stuff
Named entityHTML 2: µ
HTML 3.2: µ
HTML 4 and XHTML 1.0: µ
XML 1.0: not defined
Alt codeAlt 230
Alt 0181
Alt 181 (where cp1252-based, not a given)
String stuff
HTML/XML
numeric entities
All but basic alphanumeric encoded (hexadecimal and decimal):
µ
µ
UTF8 bytestringas hex: c2b5
(UTF8 bytestring length is 2)
URL-encoded UTF8%C2%B5
Python string
before py3k
Unicode string:
  u'\xb5'
UTF8 bytestring:
  '\xc2\xb5'
...in py3kUnicode string:
  '\xb5'
UTF8 bytestring:
  b'\xc2\xb5'
Javascript (≥1.3)"\u00b5"
LaTeX
(incomplete experiment)
Character in LaTeX:
\mathrm{\mu}
Encodings that can encode this properlyutf_8   utf_16   latin_1   iso8859_3   iso8859_8   iso8859_9   iso8859_13   iso8859_15   gb18030   mac_cyrillic   mac_iceland   mac_roman   mac_turkish   cp037   cp424   cp437   cp500   cp775   cp850   cp856   cp857   cp860   cp861   cp862   cp863   cp865   cp1026   cp1140   cp1250   cp1251   cp1252   cp1253   cp1254   cp1255   cp1256   cp1257   cp1258
Encodings that will blemish your dataascii   iso8859_2   iso8859_4   iso8859_5   iso8859_6   iso8859_7   iso8859_10   iso8859_14   iso2022_jp   iso2022_jp_1   iso2022_jp_2   iso2022_jp_2004   iso2022_jp_3   iso2022_jp_ext   iso2022_kr   gb2312   gbk   big5   big5hkscs   euc_jp   euc_jis_2004   euc_jisx0213   euc_kr   hz   johab   koi8_r   koi8_u   mac_greek   mac_latin2   ptcp154   shift_jis   shift_jis_2004   shift_jisx0213   cp737   cp852   cp855   cp864   cp866   cp869   cp874   cp875   cp932   cp949   cp950   cp1006

Layout

Note that of the ~1.1 million codepoints under U+10FFFF (the current cap), ~900K are unused, ~130K are private use, and only ~100K are general-purpose graphic codepoints (about half in BMP).
Grouping used below is somewhat arbitrary, but looks halfway sensible
For more on planes, see http://en.wikipedia.org/wiki/Mapping_of_Unicode_characters#Planes

Mouseover shows a range's codepoint range, links are to unicode.org PDFs.
Nameless gray blocks are reserved, unused or restricted areas, and show their size.
If we are showing a single codepoint above, the range it is in is bolded below.


BMP - Basic Multilingual Plane:






not allocated (63)
not allocated (63)








not allocated (15)
not allocated (79)










(End of range that UCS2(-based Unicode implementations) can store)




SMP - Supplemental Multilingual Plane:
not allocated (127)
not allocated (31)
not allocated (79)
not allocated (143)
not allocated (127)
not allocated (79)
not allocated (63)
not allocated (31)
not allocated (79)
not allocated (527)
not allocated (383)
not allocated (95)
not allocated (255)
not allocated (159)
not allocated (31)
not allocated (463)
not allocated (447)
not allocated (1279)
not allocated (2943)
not allocated (13263)
not allocated (95)
not allocated (879)
not allocated (16479)
not allocated (2815)
not allocated (4943)


not allocated (175)


not allocated (127)
not allocated (4095)
not allocated (1311)
not allocated (255)






not allocated (511)
not allocated (1791)




SIP - Supplemental Ideographic Plane:
not allocated (31)
not allocated (16351)
not allocated (1503)




TIP - Tertiary Ideographic Plane (plane 3, tentatively allocated):
Small Seal Script (tentative allocation) (10528)
not allocated (223)
Oracle Bone Script (tentative allocation) (6144)
not allocated (48639)




Planes 4 through 13 - not allocated:
plane 4 (not allocated) (65536)
plane 5 (not allocated) (65536)
plane 6 (not allocated) (65536)
plane 7 (not allocated) (65536)
plane 8 (not allocated) (65536)
plane 9 (not allocated) (65536)
plane 10 (not allocated) (65536)
plane 11 (not allocated) (65536)
plane 12 (not allocated) (65536)
plane 13 (not allocated) (65536)




SSP - Supplemental Special-purpose Plane:
not allocated (127)
not allocated (65039)




PUA-A - Private Use Area A:




PUA-B - Private Use Area B: