Learning JavaScript Data Structures and Algorithms - Third Edition

Scope variable

The scope refers to where in the algorithm we can access the variable (it can also be a function when we work with function scopes). There are local and global variables.

Let's look at an example:

var myVariable = 'global'; 
myOtherVariable = 'global'; 
 
function myFunction() { 
  var myVariable = 'local'; 
  return myVariable; 
} 
 
function myOtherFunction() { 
  myOtherVariable = 'local'; 
  return myOtherVariable; 
} 
 
console.log(myVariable); //{1} 
console.log(myFunction()); //{2} 
 
console.log(myOtherVariable); //{3} 
console.log(myOtherFunction()); //{4} 
console.log(myOtherVariable); //{5} 

The above code can be explained as follows:

• Line {1} will output global because we are referring to a global variable.
• Line {2} will output local because ...