Safe Harbor (Useful notes)

Under FCC rules, the content restrictions on broadcast TV and broadcast radio do not apply between 10:00 P.M. and 6:00 A.M. This allows "indecent" (R, and even NC-17 rated) programming to be shown uncensored on regular networks. Between 10:00 P.M.-6:00 A.M. they can play "offensive" material, such as George Carlin's "Seven Words You Can't Say on Television."

Thanks to fickle advertisers who don't want to be associated with risque content, this rule is seldom exploited. A notable exception is PBS, which, thanks to a combination of its funding system and its audience, tends to just let things fly on their post-Safe Harbor programming, particularly shows imported from Britain.

"Obscene" material (which has a specific legal definition) is still prohibited. Examples of "obscene" material would be child pornography and certain forms of hard-core adult pornography.

There are no restrictions on cable or satellite TV stations or satellite radio.

Similar to the UK's Watershed.

Examples:
 * Comedy Central shows uncensored Stand-Up and movies in their Secret Stash. Comedy Central also shows commercials for "Girls Gone Wild", phone sex networks, and pay per view porn at that time. Indeed, they broadcast one or more of these ads every commercial break after 10:00. It can get a little annoying. This has now gone through the looking glass, to where the newer stand-up acts aired during these time slots will actively reference that the viewer will likely see at least one Girls Gone Wild commercial during the breaks.
 * Although they claim that their movies are uncensored, some still are. Nudity is normally blurred out. They lie.
 * Most of the comedy specials debuted first on pay TV stations like HBO which are not covered by F.C.C. censorship rules.
 * PBS's adaptation of the play The Bridge Game, in which Mary Tyler Moore and Dick Van Dyke drop F-Bombs on each other for five minutes.
 * City TV (Toronto) and other local TV stations in Canada used to schedule soft porn late at night. Now they don't air any porn at all, ever since Rogers recently acquired City TV.
 * When Conan O'Brien moved from 12:35/11:35 to 11:35/10:35, a big deal was made about how some of his show's racier skits could not go with him. Sort of. The biggest offender everyone could think of was the Masturbating Bear, which actually showed up and did his thing on the show's prime-time Milestone Celebration in 2003. He also showed up on The Tonight Show when Conan got sick of NBC's extreme Executive Meddling. Conan's going to cable, so he'll be much freer content-wise.
 * Pretty much the point of Adult Swim, after a fashion: As noted above, the FCC doesn't regulate what cable channels show. Even so, advertisers and network executives expect that kids won't be watching TV (not even Cartoon Network) during Safe Harbor, so they're willing to let Adult Swim do what it does during that timeframe. Hell, nowadays, it sometimes airs from 10:00 PM to 6:00 AM exactly.
 * A kind of predecessor was Toonami's "Midnight Run" showing of Gundam Wing, without most of the censorship shown in the afternoon broadcast earlier in the day.
 * A careful analysis of Spike TV's advertising during the Safe Harbor reveals that the network apparently assumes its entire viewership to be male, between 18 and 30, undereducated, unemployed or underemployed, and pathetically horny.
 * To be fair that is why the channel was created.
 * NYPD Blue was one of the few network TV shows that exploited this.
 * The Swedish version of MTV used to show rather explicit music videos, such as Everybody Knows That You're Insane by Queens of the Stone Age, which featured a naked guy running around in his apartment doing... unorthodox stuff.