What are the advantages of learning html than other programming language?
Well, HTML is a Markup Language, so comparing it to other programming languages doesn't really seem to fit. If you want an answer though, it would be that you simply need a browser and notepad to write and run HTML codes, instead of being in need of installing compilers or interpreters.
html is mainly for creating basic web pages so if you learn it you should also learn other web making languages to create your own web page so personal opinion: if your going for web devolpment it is good learn html at start but if your going for other thing like android application etc... i would suggest you learn java or other languages. still learning html is a plus