Importing a file vs. opening a file
From the Welcome dialog (or the File Open command), you can only open Prism project files.
To import data from a file, you must first create a new Prism project (or open an existing one), go to a data table, position the insertion point, and then choose the Import command or click the Import button.
Prism will show you the Import and Paste Special dialog, which will let you choose whether to embed or link to the original file (Windows only), and also will let you filter and rearrange the data as you bring it into Prism.
Formats Prism can import
Prism can import text files delimited with tabs (.txt files) or commas (.csv files).
When thinking about whether Prism can import your files, distinguish the format of the file from the arrangement of the data. Prism arranges data differently than do most programs that can export .csv or .txt files.
To create a text file from an Excel spreadsheet:
Go to the worksheet (tab) you want to export, then pull down Excel's File menu and choose Save as. Select either Text (tab delimited) or CSV (comma delimited) format.
Importing csv files into Excel
If you configure Excel and Windows, you can double-click on a .csv file and have it open directly in Excel. Convenient! But it doesn't work well with some csv files (those with math symbols, Greek letters, international characters). Better to use File Open in Excel, and then choose to open a csv file from and select "65001: Unicode (UTF-8)"