Discovery devices narrow the issues of a lawsuit, obtain evidence not readily accessible to the applicant for use at trial, and ascertain the existence of information that might be introduced as evidence at trial. An attorney can prepare a "discovery packet" for your specific case.
See Attorney Rogers' response to your other question.
“Discovery” is the process whereby existing information and evidence are exchanged between the prosecution and the defense. You have a right to know what information the prosecution has in its possession. Your defense attorney will know which information must be disclosed to the district attorney and which can properly be withheld. Your defense attorney will also know which information in the possession of the district attorney should be turned over to you in return. Typically, at the arraignment, the district attorney provides the defense attorney with a discovery packet which includes the police report and other pertinent documents.
Another reason you need an attorney is because there are sometimes documents contained in the discovery packet (such as police reports containing witnesses' personal information) to which you the accused may not be entitled to see (or will be redacted).
In a criminal case, "discovery" is a general term for the police reports and other evidence to which you, or your attorney, are entitled to receive. Discovery is usually turned over at your first court appearance, the arraignment. Your attorney should have a copy of the discovery and should give you a copy as well to review. If there is sensitive information in the discovery (such as the contact information of an alleged victim), that information should be redacted, but you should still receive a copy. It is paramount to any case that the defendant review the facts in police reports and a failure for your attorney to provide you with the discovery can be malpractice.
Bottom line, your friend is right. Call your attorney and ask for a copy of the discovery. If you have a public defender, try to get a hold of him or her, and if you cannot, leave a message with your request and they should make it available to you at your next appearance.