If you want to send a photo, word document or file in Gmail, you can either attach the file from your computer or insert the file into your message using Google Drive. To insert a Google Drive file, open an email and click "Google Drive" icon located at the bottom of the email you are writing. A "Insert files using Google Drive" window opens up. You can upload a file to Google Drive as well as browse to or search for files you have stored in Drive. For files stored in Drive, select the check-boxes next to the files you want to insert. Here you have two options to send a file. You can click "Attachment" button to send a file as an attachment. This option works for files that were not created in Drive. Another option is, share the file through Google Drive. This option works for files created in Google Drive such as Google Docs, Sheets and for PDF's that you have downloaded. Select any one of the available options and click "Insert" button. Now, Gmail adds a link to your message so recipients can click the link to view your file.