Traditional publishing means you want to get published by one of the big six publishing houses in New York or one of the smaller independent presses. That means that you write the book, and then try to find an agent or submit to the publishing house directly if they accept unagented submissions. You want a bricks and mortar publisher to help you edit the book, prepare the book for print publication including the cover with cover art, and distribute it. In today’s world you have to do most of the marketing yourself. The big advantage to traditional publishing is a good editor and their access to book distribution.
Indie publishing is the new buzz word for self-publishing. Not long ago self-publishing was looked down upon by the literary world. That is changing. With the advent of the internet and new digital printing technology, one can publish in print or digital oneself for much less money than it used to take. Print-on-demand is amazing technology, which basically means your “print supplier” stores your book digitally and when a reader or retailer orders the book, the book is printed and sent to the buyer. You have to write the book, have it edited, proofed, formatted to print or digital specifications, design the cover and art, arrange for distribution and market it. It’s a lot of work. But your percentage of the book list price will be higher. It can run into several thousands of dollars to publish yourself or a few hundred. It depends what you can do yourself.