The Text mode displays the contents of a file exactly as they are stored on disk - much like an editor does.
When V opens a file, it determines whether it is a text or binary file, and displays the file in Text or Hex mode respectively. Basically, text files contain only alphanumeric, punctuation and new line characters. If files contain characters other than these, they will be displayed in Hex mode.
It takes a little bit longer for files to be displayed in Text mode rather than Hex mode. Files that are loaded in Hex mode will display almost instantaneously - regardless of size (1 byte or 500Mb). However, displaying files in Text mode is different. To display the file properly (and to handle the scroll bars correctly), V needs to know the number of lines in the file, and also the length of the longest line. As files get larger, it naturally takes longer to do this. Normally, you will not notice any delay unless the files are at least 8Mb in size.
To enable fast loading of even very large files (hundreds of Mb to several Gb), V can view files in chunks, instead of loading the entire file. Click here for further details on file chunks.
If you want V to automatically refresh a file as it is being viewed, you need to enable File Tailing.
Binary files (like ZIP and EXE files) can be viewed in Text mode, although it usually doesn't make sense to do so. If such files are viewed in text mode, many strange characters will be displayed. These strange characters correspond to non-printable (or control) characters and will differ depending on which font is selected.
Sometimes V can incorrectly decide that a text file is a binary file, and display it in Hex mode. This usually happens if a file contains an unexpected control character (eg, line drawing characters). In this case, just click on the Text icon on the toolbar (or press Alt-H) to display the file in Text mode. If you find that V is incorrectly displaying most of your text files in Hex mode, you can force V to always view them in text mode by enabling the Always Open as Text option in the Preferences Dialog box. However, by enabling this option, even ZIP and EXE files will initially be displayed as text.