These Four Noble Truths are the very Core of Buddhism.

1: This is Suffering!
Suffering is of three kinds:
a: Obvious suffering, which is any painful bodily feeling & any miserable mental feeling.
b: Suffering due to change includes also pleasant feeling as this indeed becomes quite
disappointing, when it, as it always do, changes, fades, goes away and finally vanishes.
c: Suffering due to construction is all that is conditioned and which thus later falls apart.
This also includes any object which induces a neutral neither-painful-nor-pleasant feeling.
This first Noble Truth of Suffering have to be fully understood in all aspects...

2: This Craving is the Cause of Suffering!
a: Craving for sensing various things. (Nice form, sound, smell, taste, touch, & mental state.)
b: Craving for becoming of various states. (ex: May I become rich, forever young, famous!)
c: Craving for non-becoming of various states. (ex: May I not die, not become sick & old!)
This Second Noble Truth on the Cause of Suffering have to be overcome & eliminated...

3: Absence of Craving is the End of Suffering!
a: Not craving any sensing as these fleeting stimuli are seen as gross & vanishing anyway ...
b: Not craving for any form of becoming as all states - even divine - change & decay anyway...
c: Not craving any non-becoming, but accepting what have to come (ex: ageing, sickness, death)....
This Third Noble Truth on the End of Suffering have to be made real & ever present...

4: The Noble 8-Fold Way is the Method to End Suffering!

Which Noble 8-fold Way has to be developed in order to end all suffering?

Right View (sammā-ditthi)
Right Motivation (sammā-sankappa)
Right Speech (sammā-vācā)
Right Action (sammā-kammanta)
Right Livelihood (sammā-ājīva)
Right Effort (sammā-vāyāma)
Right Awareness (sammā-sati)
Right Concentration (sammā-samādhi)

This Fourth Noble Truth on the Way to End Suffering has to be initiated and fully completed.