From the time he was in utero up through now, I've always read, sang, smiled, talked, babbled, listened to, pointed at, and loved my son. As he got older, he began communicating back with me in his own way with little babbles and squeals. We now have back and forth conversations, me talking and him babbling away. Though I don't understand what he's saying, it's important that I give him responses. That kind of interaction encourages communication and enhances his language skills that will be coming soon. This type of repetitive communication will help his language skills develop quicker as he hears the same words over and over and learns to connect them to their meanings.
A lot of people say that humans are lifelong learners, but learning is crucial for children from the point they're born up through age give. This is the time in their life when billions of connections are being made and stored in their brains. We as parents can help shape these connections through interaction and communication.
Check out this video for an example of how I interact with my son to help him develop communication and language skills.