Your goal as a database developer is to adequately protect your database and the information it contains, without imposing unnecessary restrictions on the people who use it. The type of security required to protect a database depends on how many people are using it and where it is stored.
You can encrypt a database, which does not prevent it from being opened and viewed in Access, but does keep people who don't have a copy of Access from reading or making sense of the data.
You can assign a password to your database to prevent unauthorized users from opening it. The database is automatically encrypted when you assign it a password.
If your database contains VBA procedures, you can protect your VBA code by assigning it a password, or by saving the database as an Access Database Executable (ACCDE) file. If you set a password for the code, it remains available for editing by anyone who knows the password. If you save the database as an ACCDE file, people using the file can run your code, but they can't view or edit it.
Other members of your organization can input and extract data through a SharePoint collaboration site. By making database information available through SharePoint, you can regulate permissions, track changes, and manage versioning in ways that you can't within Access.