Computer help forum: Delete button doesn't delete

Steve,
one of the ways I delete is by placing the cursor in front of a phrase I want to edit and pressing delete. Everything after the cursor disappears.
For instance, had I written 'everything after the cursor disappears from view' and I just wanted it to read 'everything disappears' - I place the cursor behing disappears and press delete to eliminate 'from view' in one step.
If it is a whole paragraph+ I want to erase, I do use two steps, highlight and then press delete. But for only a word, or a remainder of a phrase, I find it quicker to just press delete.
I realized yesterday of how much easier I find it to make changes that way, when it suddenly didn't work and I had to resort to backspacing (for a single letter or a few) or selecting a section and then backspacing to get rid of it.

Also, I couldn't delete an extra line I may have entered, i.e. between paragraphs. If I want to eliminate the line between ...of it. above and ...Also, I would just place my cursor behind ..it. and press delete to tighten up the space. I couldn't do that, either.

Hope that I explained my dilemma a bit better this time. BTW, what does AFAIK mean?

Thank you both for your prompt replies.
I turned my computer on this morning and it is responding the way it should again.
It must have had a bad day yesterday.

What was happening was that whenever I placed my cursor in front of a letter, word, or phrase I wanted to edit and pressed delete. No response.
I was using Outlook Express for e-mails when I first noticed this. It also happened for my messages in this forum.
I had to highlight and then backspace to remove anything I had written and wanted to change.

I was also unable to close (X) out my internet pages.
They would just not go away, but everything is fine again today.

I thought of the delete key gone bad as well, but was hoping for an easier solution.
Thank you both again for your interest.
Karin