Copyright
Creative Commons Licences
Creative commons is a nonprofit organization which dedicates itself to providing different simple copyright licences. To use these licences you simply have to make the licence you chose visible on you work in a way that is easily recognized by others. You can find more information on the topic here.
Which licence should you use?
In the end the decision which licence to choose is yours. Creative Commons offers a chooser which recommends you a licence based on your needs. But for example the DEAL-Consortium recommends the use of CC-BY licences of Open Access publications. The use of NC-licences (non-commercial) is not recommended. You can find a more detailed overview of the problems of NC-licences in the context of Open Access here.