Tight hamstrings are extremely prevalent in a lot of people, and completing a simple stretch or two a day can help reverse or prevent them from becoming an issue.
Tight hamstrings can be a causing factor for back pain, giving your discs in you low back especially a torid time. Your hip flexors and hamstrings play a big role in the stability of your spine (especially the lumbar region), and when tight can cause your low back to bend forward, which in turn puts pressure on the discs.
These two stretches are safe when done with good form, the stretching leg should be kept straight and you should aim to keep your back as neutral as possible when performing them. It is good practice to integrate this into your daily routine, only 30 seconds on each side is needed. If your hamstrings are particularly tight, I would suggest doing at least 3 reps per side.
Why not try these out and see how you get on!