Electrical resistivity and conductivity are ways we measure how electricity flows through different materials.
Resistivity is a measure of how much a substance resists or blocks electricity when it is passed through it. Materials that have high resistivity, like rubber, don't let the electricity flow through them easily. Materials that have low resistivity, like metal, let the electricity flow through them easily.
Conductivity is a measure of how well a substance carries electricity. Materials with high conductivity, like metal, let the electricity flow through them quickly, while materials with low conductivity, like rubber, don't let the electricity flow through them quickly.