When inspecting concrete, it's important to look for several key features to ensure that the concrete is in good condition and safe to use. Some things to look for include:

1. Cracks: Look for any cracks in the surface of the concrete, as these can indicate structural problems or issues with the foundation.
2. Surface discoloration: Concrete can discolor over time due to exposure to the elements or other factors. This can indicate that the concrete is deteriorating and may need to be repaired or replaced.
3. Surface roughness: Check the surface of the concrete to see if it is rough, as this can indicate that the surface is breaking down and the concrete is becoming weaker.
4. Spalling: This is when the surface of the concrete starts to flake or peel away, which can weaken the structure and make it more susceptible to damage.
5. Deformation: Check for any deformation or sagging of the concrete, as this can indicate that the concrete is settling or shifting and may need to be stabilized.
6. Efflorescence: This is a white powdery substance that can form on the surface of the concrete and can indicate that moisture is seeping into the concrete and causing damage.
7. Popouts: Look for any small, circular holes in the surface of the concrete, as these can indicate that the concrete was not properly mixed or poured and may need to be repaired.

It's important to address any issues you find during your inspection promptly, as they can lead to more serious problems and potential safety hazards if left unchecked.