NonSerialized Manual     Reference     Scripting  
Scripting > Attributes > NonSerialized
NonSerialized Class, inherits from Attribute

The NonSerialized attribute marks a variable to not be serialized.

This way you can keep a variable public and Unity will not attempt to serialize it or show it in the inspector

// p will not be shown in the inspector or serialized
@System.NonSerialized
var p = 5;

class Test
{
// p will not be shown in the inspector or serialized
[System.NonSerialized]
public int p = 5;
}