It defaults to Sheet1 in the open workbook which is Book1.
what part of the window shows the name you opened
Object Window...
To start a program click start, and then click the name of the program you want to open. The selection of the start menu that you will see displays the icons and names of the most recent and most frequent used programs. To open a program that you do not see on the start menu, point to Programs, and then navigate through the menus to the program you want and click it. When you open the program, Windows automatically displays it on the start menu.
Window
Double click the document name in an explorer and if you have a program that can open it it will open. If you want to open it with a specific program, right click the file name and select "open with" select the program you want to open it with. or Open the application, drag the document file to the application window and if the application can open it it will.
A minimised window
The "Open with" window gives you the option of selecting which program to use to open the file you have selected. jpeg is not listed because jpeg is a file format, not a program. If you clicked on a jpeg file and got an "Open with" selection window, you want to select a program that handles jpeg's, such as MS Paint, Paint Shop Pro, or Photoshop.
To find the version number of Mac software you click on the software's name from the menu bar (top left) and then About software's name from the menu. This will open a small window with details about the software.
It is within each application or program. Open the program and then click the name of the program on the top left. A drop down window will appear. Scroll down and click Properties. There is also the System Preferences which is located in the dock.
All open "boxes" like a program is considered a window in Windows. Ctrl+E for an example.
At the top right of the window there is a -, a square, and an X- means 'minimize' (the window 'disappears' from view and an icon is at the bottom, where you can bring it back)Square is 'maximize' makes the window fill the entire screen.X closes the window and may quit the program that is running that window, if no other windows are open in that program.