This is a very brief and vastly simplified version of Hungarian Notation. If you think mine is too complex here is a readable version of the original.

Hungarian Notation Prefixes
Prefix Description Example
i int int iAge
n short int int nIQ
b boolean boolean bPassed
l long int long lDistanceToStar
f float float fSalary
d double double dNationDebt
c char char cGrade
s String String sLastName
tf TextField (AWT) TextField tfName
jtf JTextField JTextField jtfName
tar TextArea (AWT) TextArea tarResults
jl JLabel JLabel jlExam1
p panel panel pUserInterface
.   .
Modifier Description Example
_ class variable (attribute) String _sLastName
xa array of x int[] iaGrades; String[] saLastNames
.   .
Exceptions Description  
loop counters As described in the style guidelines the variables i, j, k, etc. are typically used as loop counters and Hungarian notation is not used.
x Usually a short int, used for x coordinate in graphics
y Usually a short int, used for y coordinate in graphics