They run every 3-4 min. U-Bahn has 6 lines running through the city area, almost everywhere underground. They run every 10 min, every 5 min.
Buses have a large area to cover, are about as fast or slow as trams.
With buses and trams, there is probably no place in Munich more than 5 min. Buses usually run every 10 mins, but in the evening and on the weekends some lines run only every 20-40 mins. Service usually from 5 to 1 a.m. Some special lines run the whole night, every hour on weekdays, every half hour on the weekend nights . If you have a bike, you're lucky.