What's meant by slow code?

The borders interactive lesson provides a link to the wikipedia page for code bloat.

The opening sentence mentions code that’s slow.

Code bloat is the production of code that is perceived as unnecessarily long, slow, or otherwise wasteful of resources.

What exactly is meant by slow code?

exactly what is says? The code takes a long time to execute because it isn’t written effectively, a good example is here:


they are visual representation of sorting algorithms, now that might sound scary, but it simply means sorting the bars by length

as you can see, the selection and bubble sort take a much longer time then quick3 and heap3, given they are less effective

that is what slow code means


now, the universal selector is known to be slow, given it needs to select many elements (all on page), where a div css selector might only need to select one or a couple of divs on the page, which is a whole lot less work