A lot has been said about what to teach in ICT in primary and secondary education. There are serious discussions even debates about it. Much less has been said about why ICT should be taught. [1] Competences are related actions and tasks done by people (somebody is competent in a certain field if they are able to solve common tasks related to that field). ICT curricula contain these competences, together with development tasks, activities, abilities and skills, always assuming a knowledge system you can rely on. One of the most important competences, which is gathering more and more ground in primary and secondary education of dynamically developing countries, is "algorithmic thinking". This paper is aimed at dealing with its depths.