All files in our computer can be edited in Hexadecimal language. Using the advantage of it we can think different and hide our data in the hex code. Thing is when the file will be opened or the application will be executed the secret data won’t be shown until and unless it is opened in hex using some editor which usually people don’t.
Step 1: Backup the file you are going to edit.
Step 2: Download any Hex Editor freeware. I have used Hex Editor Neo.
Step 3: Install and run hex editor.
Step 4: Open the file in hex editor.
Step 5: As shown in above image enter your secret data at end of file from non Hex panel.
Step 6: Save the file and open the file normally to check.
Step 7: To view the secret data again open the file in hex editor or you can open it in any text editor if the file edited is not a text file i.e. doc, txt, rtf
Tip: Editing an image file would be more recommended than text and exe files.