Language
A Language
When you say words in a language, you are speaking a language. Not sure what that language is, but since you're saying it it must be real.
げんご
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.
今人気のプログラミング言語は何ですか？
What are the popular programming languages right now?
言語オタクたちが朝まで言語について語りつくすオフ会にさんかしてきました。
I joined an offline gathering where language geeks got together and talk about language all night long.
新しいコンピュータ言語の勉強を始めました。
I started to study a new computer language.