I was told to fix my crack!

No, really, this is a common recommendation for home inspectors to make about walkways and driveways. What type of crack were you thinking of?
 
Walkways made of concrete and driveways constructed from concrete or asphalt will crack. It's inevitable and expected; granted, concrete will tend to crack more than asphalt. 
Why is sealing cracks so important?
 
It’s all about water! We want to prevent water from seeping into the cracks, as this can cause additional cracking, subsidence, and erosion of the soil underneath. When water enters, it can wash away the supporting soil, and during winter months, it can freeze in the cracks and beneath the walkway or driveway. The freezing water expands the cracks and, in some cases, lifts the area. Therefore, sealing aims to slow down, limit, or stop the water from causing further damage.
 
So, stop exposing your crack and seal it properly!
Several products are designed for sealing cracks in concrete driveways and walkways. They are typically available in gray, tan, or brown to match your existing surfaces. Before sealing any cracks, I recommend lightly pressure washing my driveway with a commercial cleaner to remove oils and stains. After drying it for a day or two, I would seal the cracks. 
 
Once the cracks are sealed, you should seal the entire driveway and walkways with a quality concrete sealant! Not only will it help maintain the surface of the concrete, but it will also enhance the overall appearance. Be sure to follow the instructions on the products you choose to use.  

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