Nofollow is like having your mom put a sticker on your shirt that says "don't talk to me" when you're in a big group of people.
On the internet, it's like a special tag that website creators put on links to say "hey, Google, don't follow this link and don't give it any credit".
You might wonder why someone would do this. Well, it's because some links on the internet are not really useful and can actually be bad for the website's reputation. For example, a spammy website or a site that sells fake products might link to another website just to try and trick people into buying their products.
By adding a nofollow tag, the website creator is telling Google to ignore that link and not give it any SEO (Search Engine Optimization) value. This means the spammy website is less likely to show up when someone searches for a particular topic or keyword.
So, in summary, nofollow is like a tiny marker that tells search engines not to count a particular link as a point for a website. It's helpful because it can prevent spammy, low-quality websites from getting too much attention and ranking higher in search results.