"&&" is Logical or Boolean Operator.Its called Logical (AND).

"&" is Bitwise Operator.Its called Bitwise (AND).

Logical (AND) "&&" can be used to compare different types of expressions.

:- Let a=10; b=5; c=0;

(a==10) && (b>a) -----> true && false ------> false so 0 (zero)

(a==10) && (b true && true ------> true so 1 (one)

 a       &&    b      -----> true  &&  true    ----->  true    so   1 (one)

 a       &&    c      -----> true  &&  false    ------> false    so   0 (zero)

Bitwise (AND) "&" is used on integers only and they are used for operations on individual bits.

Let a== 3 --> 00000011 (In Binary); b== 5 = 00000101 (In Binary);

 3 --> 00000011 (In Binary)
     5 --> 00000101 (In Binary)
-------------------------------------------

& 00000001 (In Binary) so 1 (one)

:-) keep smiling and solve problems...!