Following love, the second Fruit of the Spirit is joy — chara in Greek. The King James version translates chara differently throughout the New Testament. The overarching term, expressed also as gladness or joyfulness, speaks to happiness that goes beyond the ephemeral, worldly happiness. The joy offered through believing in Jesus is deep and sustained.
Worldly happiness through your own performance, pleasure or possessions is not the joy referenced by Paul to the Galatians. Instead, joy allows you to maintain a positive attitude and a long-term happiness even through trials and hard times.
1 Thessalonians 2:19-20
19 For what is our hope, or joy, or crown of rejoicing? Are not even ye in the presence of our Lord Jesus Christ at his coming? 20 For ye are our glory and joy.