Tax contributions are divided into two categories: improvement contributions and social security contributions. Improvement contributions increase the value of a private individual's property and are obligatory payments to the State for public utility projects. Social security contributions are levies by certain public or semi-public organizations to ensure their autonomous operation and serve a social purpose.
Pecuniary benefits to non-territorial public institutions are akin to regular taxes due to their coercive nature, but they may also involve special rates and contributions, blurring the lines between public and private law. Each contribution demands careful examination.
These contributions can be seen as taxes because they benefit the entire community in the case of improvement contributions, while parafiscal contributions benefit specific professional or social groups. The distinction lies in the distribution of benefits, with one serving the collective and the other targeting defined groups.