If you ask me to give a direct one-word answer I would say it 'DEPENDS'.
What does it mean?
Yes, there is no sure answer to that question.
Let's say you are in the business of selling t-shirts. You decided to sell them online. You have two options now. Creating a web site and optimizing it for search engines. The second option is to run PPC ads and get sales.
Let's say you've chosen to go with SEO.
Now you are trying to rank for the keyword 'buy a t-shirt online'.
You are most likely going to fail because your competitors like Amazon are dominating such buyer keywords.
Whereas if you run a PPC campaign in ad platforms like Google or Bing the chances of getting success are very high.
Now in another case, if you are trying to run an informative blog, then it makes more sense to SEO your blog. Where you can find less competitive keywords and you can rank articles for that low competitive keywords.
Now you have a pretty good idea of choosing the right marketing tactic for your business.
So let's see what are the major differences between SEO and PPC.
SEO ranking and getting traffic from search engines takes months of hard work. Whereas with advertising on platforms like Google, you can start getting traffic in hours.
Traffic generated through SEO is very much consistent after your website ranked for your targetted keyword. The SEO traffic can last from months to years. But with PPC you have to keep spending money on ads to generate consistent traffic.
Most of the businesses make will creating strategies that suitable for both SEO and PPC campaigns to get the best of both tactics.
This is just an overview of both SEO and PPC. Once you learn how to use these marketing tactics you'll be able to fully understand how to use them in your business.