One challenge in understanding Joomla, particularly if you have built websites before using static HTML, is the separation of content and layout. You can display the same content in multiple ways and I demonstrate my preference in the full tutorial series. The following is an explanation of the layout options available for category/section/frontpage blog layout. You will find this helpful the next time you create a menu item, or you can edit the layout of your existing items.
The options I am referring to can be found in the right column under Parameters (Basic). The first option, Leading, refers to the number of full width articles. If this is set to 2, the first two articles will be displayed at full width, as opposed to columns.
Intro articles are displayed underneath the leading articles. If you have articles where you have used the "read more" feature, only the first part of the article (the content before the read more link) will be displayed. Intro articles can be displayed in Columns if you have entered a value for that option.
Lastly, Links refers to additional articles that appear underneath the leading and intro articles. Just the article headlines are displayed which are linked to the full article.
In the above diagram, Leading is set to 1, Intro is 4, Columns are 2 and Links are 4.
You can specify a zero setting if you wish. For example, I don't use columns much and I don't need the links feature so my settings tend to be Leading 10, Intro 0, Columns 1, Links 0. This displays up to 10 full width articles. If there are more than 10 articles, Joomla automatically inserts additional pages and includes Next and Previous navigation links.
Have a play with these options to see which is best for you and your site design.