Free is a term that can be used as adjective to qualify the free or as adverb to allude to what no cost. What is free, as long as it is achieved, carried out or offered of grace.
Something for free, like this, does not have price as it is granted or dispensed without economic compensation. However, it is important to consider that certain products or services that are mentioned as free, in reality, demand some type of consideration or disbursement.
Take the case of a technology company that invites you to create a free email box and to use it without maintenance charges. Said account may be free for the user in terms of money, but in reality the company profits by selling advertising to other firms and by marketing the personal data provided by those who register to use the service. In other words, attention and information generate income.
Suppose a bank decides to give all its customers a gift diary by way of gift for the end of the year parties. These agendas, thus, are free for people who manage to access them, but not for the bank that had to acquire them from a supplier.
We can also analyze the concept of free regarding the use of public space. Families can go to a park and enjoy its infrastructure for free (seats, playgrounds, drinking fountains, etc.), in the sense that they do not have to pay for it every time they approach the place. But they do make possible the existence of Park when paying taxes.