Fewer terms have been used as interchangeably in the cultural zeitgeist as much as 'coder' and 'programmer.' In fact, many newbies to the web development world see the two terms as interchangeable.
Usage of the two terms is largely indicative of the current state of technology and the cultural spaces it inhabits—mostly pop culture. It doesn't help that the line between the two does get blurry, so the confusion is understandable—but there is a distinction that's helpful (and respectful) to know!
No matter how pretty it is (and y'all know I'm petty), let's briefly dissect what is officially coding and what is programming.
Coding refers to both an amateur understanding of web development, or the self-taught rogue hacker archetype in pop culture. Huffington Post categorizes it as "a much more playful and non-intimidating description of programming for beginners" who are curious and want to learn more.
Coders are able to write and use code while primarily taking advantage of resources already available online through open source or tutorials.
Programming is the practice of writing code but in the sense of establishing and executing complex functions. Coming off years and years of studying software engineering, programmers are fluent in all sorts of languages beyond HTML and CSS.
Programmers are considered to be digital architects and are widely regarded as veterans of the industry. Respect your higher/senior-level programmers by not calling them coders!
At the end of the day, it's helpful to remember that all programmers are coders, but not all coders are programmers.