Being on vacation is fun. Waiting in long lines at the airport is not.

Over the past month, the Transportation Security Administration has screened more than 2 million passengers almost every day, suggesting that pandemic-induced revenge travel predictions have come to pass. Travelers should be prepared for busy airports and longer wait times than weve seen over the past two years.

If youve had to stand in a long security or customs line at the airport, however, you may have noticed that some people get to shorter, quicker lines with programs like TSA PreCheck , CLEAR and Global Entry .

But whats the difference between these three options? Read on for a breakdown and some advice for determining which is best for you, if any.

What is TSA PreCheck?

The Transportation Security Administration runs an expedited security program called TSA PreCheck for travelers departing U.S. airports.

TSA PreCheck membership gives access to a different (and usually shorter) security line at the airport with a less invasive screening process. For instance, you dont have to remove your shoes, belt or light jacket, and you can leave your laptop and approved liquids inside your bag.

TSA PreCheck members also tend to walk through traditional metal detectors rather than full-body scanners. More than 200 U.S. airports and 80 airlines participate in the program, so you can only access these benefits if youre flying out of the U.S. with an approved carrier (though the odds are good, given those high participation numbers).

In most cases, your TSA PreCheck screening will involve a separate line, but if a designated security lane isnt available at that airport, youll have to wait in a standard line. You can check the TSA website in advance to find out if this will be the case. But even if you have to go through a standard line, your boarding pass will note that you are a TSA PreCheck member, and you may be able to keep 3-1-1 liquids and laptops in your bag, and shoes and light jackets on, the website notes .