BINARY

Specifies a string of twin hexadecimal values. (Registry type REG_BINARY)

Example:

REG BINARY HKCU\Software\sunw\cc\1.0\sunwnfs 
Binary_test 7465737400

MULTI

Specifies a set of strings separated by spaces. (Registry type REG_MULTI_SZ)

Example:

REG MULTI HKEY_CURRENT_USER\Software\Netscape\MyKey 
Srtings
"My telephone number is 1234567"
adds the strings My, telephone, number, is, and
234567 to the value Strings.

STRING

Specifies a string. (Registry type REG_SZ)

Example:

REG STRING HKEY_CURRENT_USER\Software\Netscape\MyKey
test Hello
adds the string Hello to the value test.

WORD

Specifies a integer in decimal or hexadecimal format. (Registry type REG_DWORD)

Note: 

When a decimal number is entered it will be converted to hexadecimal and stored. When read back it will be in hexadecimal format, and leading zeros will be added to look exactly as it does in the Registry. 

Example of writing a decimal value:

REG WORD HKCU\software\netscape\MYKey MyValue 
4294967295
SET errorcode=%SNERRORLEVEL%
IF NOT "%ERRORCODE%" == 0 GOTO ERROR

Example of reading the same value:

SET REG readvalue=HKCU\software\netscape\MyKey MyValue 
NOTSET
IF NOT ERRORLEVEL 0 GOTO ERROR2
ECHO Value read is "%READVALUE%"