Apple ships its OS X operating system with a number of utilities and tools that can be used to troubleshoot problems with the system and third-party devices, as well as help configure the system for specific uses.
Many of these tools, such as Disk Utility, are available in the main Applications folder, and the Applications > Utilities folder, but Apple also has a number of hidden options. Some of these are Terminal-based commands which in the hands of a competent and versed user can be exceptionally powerful for diagnosing problems, fixing them, and configuring the system. Others are hidden in the system's CoreServices folder.
The CoreServices folder is located in the Macintosh HD > System > Library folder, and contains a number of applications, background tasks, and shared resources that the system uses to provide various services to the user. For example, this folder contains the Captive Network Assistant tool, which will launch when you connect to a Captive Network Wi-Fi hotspot and need to provide login credentials.
While a number of the utilities in this folder are meant to only run in the background and do not have any user interface elements, there are a few that do have these features and support options for opening directly and providing some utility to those who need them. Some of these include the following:
- AddPrinter: Interface for configuring a new printer; generally launched from the Print & Scan pane of System Preferences
- Archive Utility: Simple file compression tool; used limitedly by the OS for compressing and expanding Zip archives in the Finder
- Certificate Assistant: Helps create and manage digital certificates for network service access
- Directory Utility: Manages OpenDirectory and ActiveDirectory domain access; generally launched within the Users & Groups pane of System Preferences
- Folder Actions Setup: Configures and binds AppleScripts to folders; generally in the AppleScript menu extra (enabled in the AppleScript Editor utility)
- Network Diagnostics: Checks Wi-Fi and Ethernet connectivity, and suggests solutions for problems
- Network Setup Assistant: Sets up your systems networking configuration
- Screen Sharing: VNC client generally launched from selecting a shared computer in the Finder sidebar and clicking "Share Screen..."
- System Image Utility: Creates netboot images of a computer; generally used for networks configured with OS X Server
In addition to these directly in the CoreServices folder, there are a few others in a subdirectory named "Applications." These include the following:
- Network Utility: Apple's classic network tools utility, which include netstat, ping, finger, and lookup services along with information about your network interfaces
- RAID Utility: Configuration tool for Apple RAID arrays attached to the local system
- Wireless Diagnostics: Wi-Fi-specific diagnostics tool that is somewhat redundant with the Network Diagnostics tool in the parent directory
While you can still launch these tools from respective service interfaces such as System Preference panes, they can also be launched directly if needed. One approach you can take is to make aliases for them in the Applications or Applications > Utilities folders by dragging them with the Command and Option keys held. When you do this, the dragged icon of the program will adopt a small curved arrow indicating an alias will be made when the mouse is released, instead of moving or copying the item. Do this for all of the tools you desire, and you should be able to access them.
One additional tip here is to use your home folder's Applications folder instead of the main one at the top level of the file system, especially if your system is accessed by more than one person in separate accounts. Create a folder in your home directory called "Applications" and then make your aliases in here. This folder should adopt the same "Applications" icon as the main Applications directory, and be treated similarly by many programs and services (such as Spotlight, if you use it to find and launch programs). The benefit of doing this, is that the CoreServices program aliases you put in here will only be available to your account, instead of to everyone on the system.