Answer:
The answer to your question needs qualifying: There is significant debate among Christians as to whether the speaking in tongues, or glossalalia, as recorded in the fifth book of the New Testament is the initial indicator (or outward sign) of the baptism of the Holy Spirit or the operation of one of the nine spiritual gifts of the Spirit, or is the gift of tongues as referred to in 1 Corinthians 12:10. Other sects believe that the tongues spoken in the Acts of the Apostles is not a gift at all but the use of a learned foreign language for the purpose of evangelization.
The tenets of some Christian sects, i.e. Pentecostals, state that the speaking in tongues recorded in the Acts of the Apostles is the initial sign of the outpouring, or baptism, of the Holy Ghost. They would state that the gift of tongues (in 1 Corinthians 12-14) is not mentioned here because of the lack of interpretation of the tongues, and quantity of participants uttering the tongues (more than two or three). Non-Pentecostal Christian faiths believe that it is not the initial sign of the Holy Spirit, and that it is the gift of tongues being recorded as was stated in 1 Corinthians 12:10.
Some religions believe that these instances of speaking in tongues were single, or multiple, cases of people speaking foreign languages where the speakers and hearers of the tongues spoke and understood the languages being spoken for the express purpose of evangelizing non-believers. Nonetheless, speaking in tongues is recorded three times in the book of Acts of the Apostles: In chapter two, verses three through four, chapter ten, verse 46, and chapter 19 verse six.