Gasoline-powered chainsaws combine power and mobility. They range from light-duty models to professional-grade saws that can fell large trees. A gasoline-powered chainsaw cranks with a pull-start and has a two-cycle engine that operates on a mixture of oil and gasoline. You mix the fuel yourself or purchase premixed fuel.
Electric chainsaws are good for small jobs — trimming, pruning and light cutting — requiring less power. They're quieter than gasoline-powered saws, easier to start and require less maintenance. You'll find both corded and cordless varieties.
A cordless saw offers better mobility, and recent improvements in voltage and batteries have greatly improved performance. But the battery still adds weight and limits operating time. You may need to recharge the battery or swap it with a fresh one, depending on the amount of work you're doing.
A corded saw is lighter and doesn't require you to refuel or recharge. It does require a suitable extension cord that reaches the work area, so you may need to factor this into the cost. Your work area is limited by cord length, and you have to keep the cord out of the way as you work. Follow the device manufacturer's instructions for selecting a compatible extension cord and see Power Cord Safety Tips.