Infant baptism is a practice common to many denominations, orthodox and heretical. Personally, I was raised in a primarily Anglican setting. It is believed that my father may have had me baptised as a baby, but this is unproven. What I do know for a fact is that I was told one had to be "Christened" (the Anglican form of infant baptism) to be a Christian.
While many denominations practice infant baptism, we know, from the word of God, that it is not part of the Christian faith. This is because of the purpose of baptism. Baptism is "...(not the removal of the filth of the flesh, but the answer of a good conscience toward God), through the resurrection of Jesus Christ" (1 Peter 3:21). Infant baptism undermines this, as an infant cannot give an answer of good conscience towards God. An infant, of course, has no conscience. Baptism, to them, is just a meaningless sprinkle of water.
The Bible describes many instances of baptism, none of which explicitly involve children too young to believe. Rather, every example of baptism given in Scripture is a direct response to belief. The three thousand souls in Acts 2:41 gladly received the faith before getting baptised. Simon was baptised after he believed. Crispus and the Corinthians were baptised because they believed. You will not find one airtight example of a baby being baptised, because a baby can't believe (and there is sufficient Biblical evidence to suggest that a baby doesn't need to either, as they are no more capable of sin than of repentance).
Infant baptism is, at best, a useless gesture. It is a ritual that rearranges what baptism is, even to the point where many believers do not receive baptism for real. Infant baptism does nothing for the child, or for the faith. What it does do is shift the definition of baptism so that those who are less inclined to study the Scriptures might be confused as to the purpose of baptism and the nature of salvation. Therefore, the practice is more spiritually harmful than beneficial, and so while it is not an issue worth dividing over, it is certainly an issue worth taking seriously. It is important to reject infant baptism as a man-made, theologically ignorant tradition.