for samatha meditation yea, got about 40 taught by the Buddha.

Not all of these meditations are suitable for everyone. It depends on your temperaments (past karma, tendencies, affinity, etc).

However, there are universal meditation such as MEtta (loving-kindness). This one is suitable for all types of temperaments, because deep inside all of us, there is a lot of hatred in our subconscious.

The effect of meditation is not something like a one-time fix.. but gradual. It has to be applied in daily life too.  Meditation serves as some positive reinforcement into the subconscious - everyday we tell ourselves to be loving-kindness to all being, slowly slowly over years, over decades,  you find your level of hatred reduces.....

For example, playing video games like dOta or Wow... They look harmless.. but if the individuals play those games, they got angry when TMNET down , or they got killed in Dota by their friends, they got angry..... on daily basis.  slowly, day by day , that person gets angry for about 10 mins everyday.... over the years... he finds himself become a very hostile person in real life... easily get irritated, angry, etc.

I am talking from real experience.

So this mental conditiioning is very gradual... if we want to become a good person , we need to do it daily, slowly... everyday throw away some bad habits.. over time, over years, over decades, we will succeed.

By the time of death, we will be a very happy person and calm person. At that time, our 'habitual kamma' is that of a person with very much reduced hatred/anger.. and this kamma will help to help us avoid those destinies associated with these hatred based kamma --> hells, demons who fight each other, animals.....

so i hope this helps you to get a brief idea on meditation.

No need to look very far or greedy... some people meditate they want to attain Jhanas (their sole intention), but when they cannot attain it (not realizing that practice of dhamma comes altogether with Good morality and dana too).. they got pissed with buddhism and dismiss it as 'false'  I met these types of people. Motivated by greed and hatred they approach buddhism.

We shouldn't go that direction.