What are discretionary access controls?

What will be an ideal response?

DACs are implemented at the discretion of the data user. The ability to share resources in a peer-to-peer configuration allows users to control and possibly provide access to information or resources at their disposal. The users can allow general, unrestricted access, or they can allow specific individuals or sets of individuals to access these resources. As an example, suppose a user has a hard drive containing information to be shared with office coworkers. This user can allow access to specific individuals by listing their names in the share control function. Most personal computer operating systems are designed based on the DAC model.