The roots of concise confessional formulas reach back into Scripture itself. The Shema in Deuteronomy 6:4 and Paul's summary of the gospel in 1 Corinthians 15 show that God's people have long confessed the faith in brief, memorable form. The early church continued that pattern by gathering foundational Christian teaching into a compact baptismal confession.
The Apostles' Creed developed especially as a baptismal creed. Catechumens learned these articles as the essential truths of the faith, publicly confessed them, and then received baptism. In that way the creed functioned not only as a doctrinal summary, but also as a living part of the church's worship and reception of new believers.
Its articles gather together the basics of the Christian faith: God the Father, Jesus Christ, the Holy Spirit, the church, forgiveness, resurrection, and everlasting life. Closely related to what the early fathers called the regula fidei, or "rule of faith," it remained one of the church's central creeds through the medieval period and the Reformation, and it continues to serve as a clear summary of apostolic Christianity.