# assigning values

Use an equal sign to assign values to variables.
 i1 : x = "abcde" o1 = abcde i2 : x o2 = abcde
Before assignment, any reference to a variable provides the symbol with that name. After assignment, the assigned value is provided. The variable created is global, in the sense that any code placed elsewhere that contains a reference to a variable called x will refer to the one we just set.

It is important to distinguish between a symbol and its value. The initial value of a global symbol is the symbol itself, and the initial value of a local variable is null. One possibility for confusion comes from the possibility of having a symbol whose value is another symbol; it's even more confusing if the two symbols have the same name but different scopes, for example, if one of them is global and the other is local.

 i3 : y o3 = y o3 : Symbol i4 : y = z o4 = z o4 : Symbol i5 : y o5 = z o5 : Symbol i6 : z = 444 o6 = 444 i7 : z o7 = 444 i8 : y o8 = z o8 : Symbol
In the example above, the final value of y is the symbol z, even though the symbol z has acquired a value of its own. The function value can be used to get the value of a symbol.
 i9 : value y o9 = 444
The operator <- can be used to set the value of a symbol. This operator differs from = in that the symbol or expression on the left hand side is evaluated.
 i10 : y <- 555 o10 = 555 i11 : y o11 = z o11 : Symbol i12 : z o12 = 555 i13 : y = 666 o13 = 666 i14 : y o14 = 666 i15 : z o15 = 555
One reason the user needs to understand this concept is that assignments with the operator <- are occasionally done on the user's behalf by bits of code already in the system, for example, when creating a polynomial ring the prospective variables are given new values that are the generators of the polynomial ring.