Acts 19:6

And when Paul laid his hands on them, the Holy Spirit came on them and they began speaking in (unknown) tongues (languages) and prophesying.  

The gift of tongues is a powerful prayer tool and a blessing given to us by God.  There is nothing to fear or strange about the God kind of prayer language.  When we pray in tongues, we pray for things that can only be seen on the spiritual level.  This type of prayer breaks barriers and allows us to gain wisdom and insight.