C++ :: Error C2061 / Syntax Error - Identifier (string)

I've just recently started to learn C++, and I'm encountering some errors I can't seem to figure out.

InventoryItem.h:

Code:
#pragma once
class InventoryItem {
public:
InventoryItem(string name, int amount);
~InventoryItem(void);
string getName(void);
int getAmount(void);

[code].....

Errors:

Code:
1>d:c++consoleapplicationconsoleapplicationinventoryitem.h(6): error C2061: syntax error : identifier 'string'
1>d:c++consoleapplicationconsoleapplicationinventoryitem.h(8): error C2146: syntax error : missing ';' before identifier 'getName'

[Code] .....