No programming required. Immediate data capture and data analyzing capability including fourier transform and many other functions. See here for a description of FreeVIEW plus . Not every measurement that can be performed using a full-featured data acquisition card can be also done by a sound card. DC voltage measurements are not possible.
Sound cards use capacitors in the signal path, so any DC level is removed.
This means also that there is a lower frequency limit because of the highpass characteristic of the capacitor in line. The lower cutoff frequency is card dependent. The input impedance is low. Measurements are done using the line input. Real data acquisition cards have impedances of 1 to 10MOhm.