where are the paths for the environment variables mac code example

Example 1: which path variable should i use in mac

export PATH=$HOME/bin:./node_modules/.bin:$PATH

Example 2: mac set environment variable

HIMANSHUs-MacBook-Pro:~ himanshu$ export JAVA_HOME=/Library/Java/JavaVirtualMachines/jdk1.8.0_131.jdk/Contents/Home