We are Baptists because we believe that Baptists hold to what the church, as established by Jesus and his Apostles before hundreds of years of man-made tradition and corruption. 

Baptists hold to certain core beliefs that are different than other denominations.  These teachings can be remembered by the Acronyms of BAPTISTS.

Biblical Authority

Autonomy of the Local Church

Priesthood of All Believers

Two Ordinances 

Individual Soul Liberty

Separation of Church and State

Two Officers

Salvation by Grace Alone, through Faith Alone in Christ Alone.

What that means

• Biblical Authority - We believe that the Bible is the final authority for what we believe and how we act.  There is no authority higher than the Bible.  Pastors, deacons, church tradition, church councils, etc. all must submit to the clear teachings of the Bible.  We support what we believe by the chapter and verse of the Bible.
• Autonomy of the Local Church - Each and every Baptist church is independent. There is no higher organization telling that church what to believe or what to do.  While Baptists form associations, fellowships, and alliances, these are just groupings of churches that work together in a somewhat organized manner for things like missions.  Sometimes, they form conventions, which are more official, organized groupings with a more formalized structure.  Conventions often run other ministries, like seminaries or mission boards.   Even in a convention,, each church does what it likes, owns its own buildings, and can choose to withdraw from any convention, fellowship, or association at will.
  
• The Priesthood of All Believers - Many churches have a laity (normal people) and a clergy (the priests, preachers, etc.)  This is not found in the Bible (Remember what we said about Biblical Authority?)  We believe that every saved man, woman, boy or girl can go directly to God.  We do not need an intermediate.  We believe that we are all priests.  That's not to say that we don't have leadership, but a Pastor is just a believer who God has called to bring His Word and care for and lead His Church.  
• Two Ordinances - The Bible teaches that Jesus set up two rituals or ordinances to be observed in the church.  They are Believer's Baptism and the Lord's Supper.  Some church calls these "sacraments" and teaches that they play a part in our salvation.  We don't believe that.  We call it Believer's Baptism because the only people we see in the Bible who get Baptized are those who trusted Jesus as their savior as an outward representation of what happens inside of us when we are saved.  It also identifies us with Jesus.  Since we don't see anywhere where in the Bible where it teaches that Baptism is performed by any other method other than dunking, that's the only form of Baptism we recognize.  The very word, Baptize, literally means dunked under water.  Does it make sense to say "I was dunked by sprinkling."?  The Lord's Supper, or Communion, is where we eat the bread and drink the wine (well, we use grape juice.  Usually Welch's) as a memorial for the great sacrifice Jesus made to save us.  The bread and wine do not magically turn into the literal body and blood of Jesus.  It's a symbol, reminding us of what it cost to make us free.
• Individual Soul Liberty-  Every person is free to choose to be saved or choose to reject God.  We are also free to read and interpret the Bible on our own.  I can't force anyone to be a Christian, it has to be a free choice by that person.  Likewise, I can't make a Christain behave or believe a certain way.  Each person will stand before God, and each person is responsible for his or her own devotion to God (or lack thereof.)
• Separation of Church and State - Since salvation is a matter of personal decision,  we don't believe that it is the role of the government to force a certain religion or religious practice on us.  We believe the government ought to stay out of the church, but we don't believe that believers ought to stay out of government. Baptists do not force their beliefs on anyone since that would violate individual soul liberty.
• Two offices- The Bible mentions only two offices in the church. That's the pastor (also called the elder, or bishop) and deacons.  The pastor is the shepherd of the congregation.  He leads them, teaches them, and protects them.  While we believe God calls men to preach, we also believe that each congregation chooses their pastor.  Deacons are the servants of the church, who attend to the physical needs while the pastor attends to the spiritual.  The congregation chooses out men from itself to serve in this capacity.
• Salvation by Grace Alone, through Faith Alone in Christ Alone.- We believe that the Bible clearly teaches that we are saved when we place our faith in Jesus.  It is not about doing good works, although that should be a result of real saving faith.  We are saved by grace, which means unmerited favor.  God saves us because of who He is, not because of who we are or what we have done. Our faith is to be in Jesus alone.  Not in Mary, the church, the pastor, or ourselves.