Operating Systems Scavenger Hunt
         Kelley Katzenmeyer

	An operating system is like the boss of the computer. It keeps track of everything, and makes sure every program is doing it's job. The operating system is also like a postal service- it takes data into the computer (typing on the keyboard, movements of the mouse) and delivers messages to the running applications and processes. The operating system for Imacs is called Mac OS X. When an apple computer first starts up, it automatically opens a default program called "Finder". Finder helps users sort and access files through a Graphic User Interface (GUI). However, Finder is not the only way to manage your files. Terminal can also be used, and is often more effective then Finder. Terminal uses text commands to sort through files, set permissions, and execute processes. Terminal has all  the capabilities of Finder, but Finder doesn't have all the capabilities of Terminal. On the bright side, Finder is easier to learn how to use, because of it's GUI.
	Terminal and Finder are both used to manage files. Files are bits of data stored on a computer's hardrive or memory. Not all files can be executed, like a program. However, a program is still a file. Files can belong to different people, depending on who made them. Some people don't want strangers snooping around in their files, so they set permissions. Permissions control who can write, read, and execute certain files. The owner gets to decide who can do what. The permission mode of a file can be changed on both Finder and Terminal. On terminal, you have to use the command "chmod", and a three digit code. The first digit determines what the owner can do to the file (read, write, and/or execute), the second for the user's group, and the third for the world. (The world just means everyone else.)
	Terminal and Finder can access applications, which are programs run by the operating system. Applications have specific jobs, which they may assign to processes. The Applications folder on every eMac is by an administrator. When an apprentice logs into an eMac, the path of their home folder is /home/(username).  The path can also just be defined as "~". However, all the data isn't located on the actually computer an apprentice is using at the time. Physically, it's among the many hardrives in a small glass room across from the apprentice room. An apprentice can only modify files in their home folder.
	All jobs carried out on a computer are made possible by processes. Processes do specific jobs that can come together to create a program or application. To find out what processes are running on your computer, you can use Terminal or the Finder. On Finder, open Applications, Utilities, then Activity monitor. It automatically lists what processes are running on the computer. To figure it out on Terminal, open a new shell and type the command "ps". Or, you can have it just list the processes for a certain user. To do this, type "ps -U username".  Another useful option with the "ps" command is "-u". This will show you who owns a process. By doing this, you can discover who owns the Dock process on the machine, which is the apprentice. This allows the apprentice to quit, or kill the dock. To do this, it is helpful to locate the Dock. Type "ps -U username".  Read through the files until you see one containing "Dock". The Dock process's location will be displayed, and specifically it is "/System/Library/CoreServices/Dock.app/Contents/MacOS/Dock -psn_0_786433". Also displayed will be the Dock's PID, or process identification number. To kill or quit the dock, type "kill " and it's PID. The Dock will momentarily disappear, then reload.
	Mac OS X has many helpful keyboard shortcuts. A few of these include apple z (undo), apple x (delete), apple c (copy), apple v (paste), and apple s (save). Short cuts make life on the computer easier and quicker, so instead of having to pick of the mouse and go to "Edit, Undo Typing" every time you mess up, you can just type a quick apple z.
	After working on the computer for  a while, files and projects will start to pile up. It's good to have a system to keep things organized. In my documents folder, I have created folders for every month I've been at Shodor. I sort my projects into folders based on what month I made them in. For larger projects that I will continue to work on for months to come, I create a separate folder. For example, I have a folder for my website, which is in my Documents, but not in any Month folder.