Joomla does not provide a way to format the text that appears in an article heading (such as italicising a word as I did in this article's heading). If you try to insert HTML code, this is removed when you save the article. Fix this as follows:
- Download the free extension, yvBBCode
- Install this extension as normal (see lesson 12)
- Go to Plugin Manager and edit yvbbcode
- Enable the extension and make sure the first parameter is set to Yes
- Now if you would like to italicise a word in a headline, simply include
[i] at the start of your word and 
[/i] at the end, for example:
This is my[i]italicised[/i] word
- or make it bold:
This is my
[b]bold
[/b] word