Compression and exhaust strokes are two strokes of a four-stroke internal combustion engine. The easiest way to tell the difference between these two strokes is by observing the position of the piston.
Below are the main Differences between Compression and Exhaust Stroke
During the compression stroke, the piston moves upward in the cylinder, compressing the air-fuel mixture. The intake and exhaust valves are both closed during this stroke, and the spark plug fires to ignite the compressed mixture. You can tell that the engine is in the compression stroke by feeling the pressure build up in the cylinder as you turn the engine over.
During the exhaust stroke, the piston moves downward in the cylinder, pushing the burned gases out through the open exhaust valve. The intake and exhaust valves are both closed during this stroke, and the spark plug is not firing. You can tell that the engine is in the exhaust stroke by feeling the flow of gases out of the exhaust pipe.
In summary, you can tell the difference between the compression and exhaust strokes by observing the position of the piston and whether the intake and exhaust valves are open or closed.