It’s common to believe that human rights are rights that protect us against the state. Nothing wrong there, except that it’s a gross simplification. Human rights aren’t one-dimensional. For example, there’s a difference between the vertical and horizontal dimensions of human rights: the former one describing the way rights regulate our relationship with our state/government, and the latter one pointing to the fact that it isn’t necessarily the state that violates our rights: our fellow-citizens can do the same, as can citizens of other countries. If rights had only a vertical dimension, it would be difficult, for example, to explain the mayhem caused by so-called failed states in terms of human rights violations.
With a bit of imagination, we can add a diagonal dimension: rights claims aren’t addressed only at the state and fellow human beings; corporations, cultures, associations and other groups can also violate our rights (think of corporate social responsibility, apostasy etc.). Since these entities are somewhere on a level between the levels of persons and the state, we can call this dimension diagonal.
To make things complete, we have to add a final dimension. Human rights are not bilateral, such as the rights created by a marriage contract or a commercial contract. They are omni-lateral, meaning that they are claims directed at all entities within the previous dimensions: every other human being, every state and every intermediary entity can violate our rights. That is what we mean when we say that rights are rights erga omnes.
If we put these dimensions together, we can present it graphically: every human being is situated in the center of a sphere, and the radius, wherever on the surface of the sphere it points, indicates a human rights claim.