Enter the text, images, video clips and other content for your Tumblr blog post in the Post field. Click the "HTML" button in the post editor toolbar. Tumblr switches the post editor to HTML mode.

Open the HTML source code of the Web page that contains your PayPal button in a text editor. Look through the HTML file and locate the PayPal button code that begins with the following: Insert the ...

Microsoft has created its own command line text editor. Edit on Windows is similar to vim, allowing developers to edit files directly in the command line.