Tear Jerker
"Crying is cleansing. There's a reason for tears, happiness or sadness."
Some viewers are impassive when it comes to what they watch. They've seen it all. No fictional death, sacrifice, emotional display or confession can move them.
Since most of these involve death scenes, shocking twists, or something just as major, expect many spoilers. However, they can also be as simple as the right imagery, tone, and music coming together - for the sole purpose of working those tear-ducts.
This being one of the YMMV items, one person's Tear Jerker may be another's Narm. which is often a failed attempt to induce this. Comments such as "If you didn't cry at _____, you have no soul" are not welcome here; since this is defined by emotional reaction, what causes someone to burst into tears may cause another to shrug or even laugh, and guilt-tripping people just because they don't experience the emotions you want them to is not cool.
Some tearjerking moments, especially of deaths, can wind up being traumatizing.
Contrast Heartwarming Moments. which can induce tears for more positive reasons.
Tropes that often result in Tear Jerker moments
Many Downer Endings and Bittersweet Endings include tearjerking moments. Either way, make sure to bring the Kleenex. If you want to avoid them altogether, then you might want to consider heeding the Snicket Warning Label.