In summary, the heart of an oscilloscope is the acquisition system. Analog bandwidth is the bandwidth of the amplifier at the front end, digital bandwidth is dependent on the sample rate and acquisition memory size which can affect the sampling rate. Real time sampling is good for capturing transient signals and is the default mode in most oscilloscopes. Random interleave sampling, or equivalent time sampling is only usable for repetitive signals not transients, but gives a higher effective sample rate. Roll mode is a good selection for very low frequency signals. There are many modes to start the scope such as auto trigger, single shot trigger, trigger on any of the four inputs, or an external trigger. Cursor measurements are easy to set up and are based on display resolution and the accuracy of the user placing the cursor properly. Parameter measurements offer higher accuracy, and do not rely on display resolution, or the user placing the cursor. Parameters enable the use of full internal resolution of the instrument, and the ability to display histograms or statistics on the display. Modern oscilloscopes have math capabilities including add, subtract, multiply, and etc. Fast Fourier transforms are also common. Passive probes vary in bandwidth from 100-500 MHz. Active probes are typically higher in bandwidth, much greater than 500 MHz, but require power because they are transistor based. Differential probes allow the use of one channel rather than using two single ended probes and then having to do the math, subtracting one from the other. As the name implies, high voltage probes are useful when debugging and troubleshooting high voltage power supplies. Finally, current probes are available for measuring current.