Using wordpress. When I click in the categories it shows only the links of the articles but not the articles themselves. I've seen many blogs that do that and was wondering how ?
Just use a different template. Sounds like your template doesn't include the post's text. If you're 100% against switching templates, you'll need to jump into the code. If you're not comfortable with this, let us know and someone may be able to help.
Anita was right its all about theme. Browse wordpress.com themes repository to find an appropriate template for your needs.