Abortion is always a hot topic. Some see the debate as between religious people and non-religious people, but that's hardly accurate. There are a lot of atheists who oppose abortion, for example. The question at hand is whether abortion is a moral good, a moral evil, or a neutral act.
Whether life has any real meaning is a nearly-universal question. At its core, atheism must deny that life has any objective meaning. With no God, there can be no objective meaning, so there can be no objective morality.
A worldview is simply the way we see the world: where we come from, why we're here, and so on. Jesus contrasted the Kingdom of God with the way the rest of the world works, and taught that they were very different systems. Alan Shlemon of Stand to Reason explains that witnessing to others may include not only sharing the gospel, but explaining the differences between worldviews.
