Weird characters are usually formerly-hidden control characters from a formatted document that was pasted in.

To get rid of them

• Edit your item.
• Either click on the SOURCE icon in the top-left corner of the Tool Bar just above. This will reveal all the hidden characters. Delete the stuff you don't want, then click on the SOURCE button again to show the normal format.
• Or, if you still have access to the original document, you can delete everything inside the Text Area, then start over.  Use the clipboard with the W on it or the clipboard with the T on it (icons in the tool bar above) when you PASTE in text.

To stop them from happening again

• When you paste in text from any word processing program, use the clipboard with the W or with the T on it.   Text from another webpage usually pasts in clean, so you can use the plain clipboard icon or the Control Key + V.