How to Solve an undefined local variable Ruby Error

How to Solve an undefined local variable Ruby Error In  Ruby, you dont have to declare variables, but you do have to assign something to them before they can be referred to. If youre referring to a local variable that doesnt yet exist, you may see one of two errors. Ruby NameError Messages NameError: undefined local variable or method a for # NameError: undefined local variable or method a for main:Object Note:  There might be various identifiers in place of  a  above. This is an example where the code will generate the Ruby NameError message since the variable  a  hasnt yet been assigned to anything: puts a How to Fix the Error Variables must be assigned before they can be used. So, using the example from above, fixing the error is as simple as doing this: a 10 puts a Why Youre Getting This Error The obvious answer is that youre referring to a variable that hasnt yet been created. This is most often due to a typo but may happen when refactoring code and renaming variables. You might also see the  NameError: undefined local variable Ruby error if you intended to enter a string. Strings are understood when they exist between quotes. If you didnt use quotes, Ruby will think you meant to reference a method or variable (that doesnt exist) and throw the error. So, look back over your code to see what this variable is supposed to be referring to, and fix it. You may also want to search for other instances of the same variable name in the same method - if its wrong in one place, it may be wrong in others.