Update article.md

[bruteF04C3]

undefined and "not defined" are two different things, updated for the sake of clarity

[joaquinelio]

I like the original
Not defined by the coder, so js assigns undefined

Is the only purpose of undefined type I hate

[bruteF04C3]

I like the original Not defined by the coder, so js assigns undefined

Is the only purpose of undefined type I hate

Don't get me wrong but I did not completely understand what you said.

Since "Not defined" is a reference error as well,
here this term might create confusion for some people. Also, undefined is clearly the suitable choice here.

But again, I am open to any debate over the same

Thanks !

[joaquinelio]

oh, got it, "not defined" is a common error msg
yes, it can be rewritten

sorry I have to work on my english grammar, I meant
1 I liked "not defined" as "the programmer didn't specify "user"
2 The "I hate undefined type" is just garbage I usually drop.