“A friend asked me if I spoke in tongues. I have heard of this but am unaware of what it actually is and if it is something I should do.”
The New Testament gives several accounts of people who, when “filled with the Spirit,” spoke in a language that was not their own. In one instance, this language (actually, languages spoken by several different people) were known languages recognized by others for whom the language was native. This is the well-known event at Pentecost (Acts 2:1-12).