Where can I find THAT text, to change it. Firebug??

How does one get to know where to change a certain text...

Maybe with Firebug..? But for example if I want to ask FireBug about a certain plain text it gives

Code:

---

<div id="teachers" class="mod_article block" style="margin-bottom: 24px;">
<div class="ce_text block">
</div>
</div>
<div id="helen-lewis" class="mod_article block" style="margin-bottom: 24px;">
</div>
<div id="james-wilson" class="mod_article block">
</div>
</div>

---

Than I still don't know where to look in the back end...

Firebug wont help because the content is dynamically created on the server, and firebug will only see the final page sent to the browser, but nothing about the creation process on the server.

There ist no general rule where a certain text comes from.

Variable texts:
Mostly coming from an article or a news item.
But it can also come from other sources such as comments, events, or other extensions.

Fixed texts:
Normaly created by a module.

First you need to identify what module is creating the output.
Then you will find the text in one of the files in the directory:
/system/modules/[modulename]/languages/[language shortcut]/

Website Content....Usually by editing the Content Elements in Articles on a certain page of the site structure.

Or do you mean the style of a text???
CSS...Stylesheets

No just the content. It is all so new you know I have to see if i'am intelligent enough myself... or enough to later on able to explain a client ..

Yes I find a lot of content in Articles, nowere I can find the left colum BREAKING NEWS "Jazz pianist James Wilson returns to Music Academy to give lessons in traditional and " I just can't find.. *&%^^%^$%%

I think that is not too difficult to find:

news
"Music Academy News" (click on pencil symbol)
"Associate Professor James Wilson returns" (click on pencil symbol)
Open "Subheadline and teaser"