Americans will wake up on Wednesday with new resolutions, new calendars and, in many states, new laws.

From marijuana and guns to pornography and social media, a host of laws are taking effect on Jan. 1.

Here’s a look at some of them.

Gun Laws

A law goes into effect on Jan. 1 in Minnesota that bans “binary triggers,” devices that allow firearms to fire one shot when the trigger is pulled and another when it is released. The law also bans forced reset triggers, which can make semiautomatic firearms shoot at nearly fully automatic speed. The law was passed after a man in Burnsville, Minn., killed a paramedic and two police officers in February; the man had recently acquired a weapon that with a binary trigger, the authorities said.

A number of states already ban binary triggers and other conversion kits, like bump stocks, that allow firearms to fire at the rate of machine guns. It is unclear how effective a ban might be. Hobbyists frequently use the small but often expensive devices with AR-15-style rifles. Their small size and ease of installation make it difficult to ban the devices outright.

In many cases, those who are intent on installing conversion kits find workarounds or simply ignore the law. Still, such bans, while hard to enforce, can increase the severity of charges when a crime is committed.

In Delaware, a new law makes it a crime to possess weapons on the campuses of colleges and universities, adding them to the state’s school safe zones. Many states, including California and New York, already ban firearms on college campuses in most circumstances. Most states that do not have an explicit ban allow individual colleges to decide whether or not to allow guns on campus.