"THIS"

There is an adjustable bar on my page - can anyone tell me how that was coded. I'm assuming when the question refers to "... this" that the meaning of it is that there is an adjustable bar on the page. Since I have one on every page. I'm changing my mind - I don't think "this" can actually cause me to have an error. I really like the way "this" shows up on my question. Please tell me how you coded "this"! I am very curious.