Command (data entry): The command line can be used for lots of things, including:
1) Items in the scene can be searched for and selected. Just type in the word search, then in parentheses, put the name (or portion of the name) you are looking for. When you then press enter, all items with that name or portion thereof will be selected. For example, type in: search (jp) and it will find and select all items containing jp. If you type search (SnitzEdwards.lwo) it will find and select the object called SnitzEdwards.lwo.
2) It will execute any of the Expression Functions. It's like a "one-time execution" expression field.
3) Quick calculator-- type a formula or math problem in and press Enter. The result will appear in the Message field to the right of the Command line field.
4) It's basically a Command Line Interface (CLI) to the program.