Default Parent Application
Every document on your computer should have a default "parent" application. That’s the application that will open the document when you double-click it. The document’s icon usually hints at what the parent application is (see Figure 11). A document without a parent application is referred to as an orphan and it has a plain icon.
Figure 11 Here’s the icon for a document whose parent is TextEdit.
What if you don’t want to open every JPEG file with Preview or every Rich Text Format file with TextEdit? Just change the default parent application.
Select the file for which you want to change the default parent application. Then choose Get Info from the File menu. In the Info window that appears, choose a different application from the "Open with" pop-up menu (see Figure 12). The document’s icon changes (see Figure 13).
Figure 12 The "Open with" pop-up menu lists known applications that can open the selected file.
Figure 13 When you change a file’s parent, its icon changes.
If you want all files of that type to open with the new parent application, click the Change All button beneath the "Open with" pop-up menu in the Info window. Then click Continue in the confirmation dialog box that appears. From that point forward, double-clicking that type of icon opens the document with the application you chose.