The advantages of multimedia are clear: Increased time spent engaging with the website, which means enhanced ad revenues. An article or blog post (unless it's exceptionally good) will be read only once (if it's read at all), but content such as songs, podcasts, and video can and will be viewed multiple times.
As for disadvantages, the largest one, especially with video, is that production quality has become an arms race. Modern cameras and editing suites are quite expensive. The budget-conscious web designer might be wise to lean into their strengths when designing a site, and that might call for reduced use or exclusion of video.
If there are barriers to video, you can still represent yourself well with images. The most common formats are .png, .jpg, and .gif.
A .png file allows for more unique effects, but this also calls for larger files, which increases page loading times. For simple photographs that don't require much detail, you can use a .jpg.
The .gif remains a popular format as well, as it allows for transparency, unlike the .jpg, but with the same smaller file size.
Maybe music or podcasts are your thing. If your website is predicated upon audio uploads, you might consider using .mp3 files instead of .wav files, especially if you're posting talk content. Save the .wav for a finished, fully-produced song.
The modern web rests largely upon three pillars: HTML, CSS, and JavaScript. JS is a must for certain functions, such as dynamic content. One highly appropriate use case is seen on DraftKings, where JS is used to facilitate in-game betting with rapidly changing odds every few seconds. A full refresh of the page prompted by the server would be both impractical and obnoxious to the end user.
JS functions as both a server-side and as a client-side language. In this regard, it's beneficial to the user, as this allows the code to be executed on their device, which allows them to see it as desired in their browser of choice, and it reduces the load on your server as well.
Sometimes, there are inappropriate use cases for JavaScript. It's easier to manipulate, because the interpretation occurs on the client-side, so you wouldn't want for a payment transaction to depend on it. Additionally, mathematical functions are not always performed accurately, as described in a Medium.com post from 2018. Ultimately, the best websites use JS in such a way where the differences between pages with and without JS enabled by the user are marginal.
Similar to JS, but not quite as widespread, PHP is speedy, and easy to integrate into HTML documents. The code is easy to copy and to adapt elsewhere, and PHP is free and open-source. PHP serves as the backbone of WordPress, the market leader in content management. Additionally, PHP is well-regarded for its use with MySQL, used in the ever-growing and increasingly important field of data science. With similar compatibility to JS, it would seem the only argument against using PHP would be to place the responsibility of loading a webpage onto the client, instead of assigning the task to the server.
Things to consider when choosing a host: