It has been my experience that many people do not fully understand what custody and access mean. Custody and access are the terms used by the Divorce Act and, therefore, only applies to married couples.
In essence, custody is the term used by the Court, to people involved in divorce proceedings, when referring to which of the parties has the ability to make the day to day decisions that affect the lives of the children. For example, where the children live, what school they go to, which religion they practise.
Access is the term used by the Court, to people involved in divorce proceedings, when the Court decides when each of the parties have the children. Many people use the term "custody" when they refer to "access."
For non-married parents in Alberta, who have to rely upon the provisions of the Family Law Act, guardianship is used in place of custody, and parenting is used in place of access. It is further complicated by the fact that, if married parents are not divorcing, they, too, have to rely upon the Family Law Act.