How do I include the category next to the title of a post?

you’ve already had a comment about the lack of detail, so I’ll try and guess what you want to do.

Assuming you’re inside ‘the loop’ and your title is being echo’d out with:

<?php the_title(); ?>

..then the easiest way for you to show the title first is to do this:

<?php 
$catobjarray = get_the_category(); 
if($catobjarray[0]){ echo $category[0]->cat_name;}
?>

Caveat of this method: As a post can belong to more than one category, this code will only display the first cat the post is in.

Have a look at the codex for get_the_category() HERE.