A tension headache is generally a diffuse, mild to moderate pain in your head that’s often described as feeling like a tight band around your head. A tension headache (tension-type headache) is the most common type of headache, and yet its causes aren’t well-understood.

Reference: By Mayo Clinic Staff, https://www.mayoclinic.org/diseases-conditions/tension-headache/symptoms-causes/syc-20353977, consulted on  july 1st,2019