I am going to be completely unbiased in this but I am going to include my opinion on certain music. I enjoy all kinds of music besides country but I mostly love rock and metal.
I am going to start out with my favorite first, Metal music. Metal can be alternative, nu (a mixture), softcore, hardcore, death/deathcore. Mudvayne is an example of deathcore. Their heaviest song is probably Dig or Forget to remember. Happy ? is my favorite song by them. Metal is usually about life and love and heartbreak.
Slipknot is an example of nu metal, a mixture of different genres but still classified as metal. Their softest song is Snuff and their 'hardest' song is probably Psychosocial.My favorite song by them is Killpop.
Now onto rock. Coldplay for example is alternative rock or pop rock. They're more of a light sounding band. Their best songs in my opinion is Viva la Vida and Fix you. Rock is usually about life and emotions and more serious topics.
Now hip-hop. This is a genre not most people like but i find it to be very nice sounding. An example is Ed Sheeran. He is considered hip hop, with some pop, folk and acoustic. My favorite songs by him are Photograph and Wake me up. Hip hop can be about anything from just dancing to love.
Now for some pop. Lorde is considered very popular, or just pop. She is a good singer with a nice voice. I dont listen to her as much but music thats considered pop is POPular for a reason. I find pop to be extremely catchy. Uptown Funk is very catchy and I like how he can get a bunch of people to sing positive words about themselves. Pop can be about anything, it's just whatever is popular.
Reggae is more fun and may be considered pop. It is influenced by Rastafarian ideas and may revolve around that, for example, Bob Marley. Cheerleader by OMI is considered pop reggae, one of my favorite songs of this genre. It's positive about your girlfriend (or SO in general) and to not cheat. I find it sweet and catchy.
Rap. Rap is not for everyone but many rap songs are popular, and are a mix of pop/rap. Rap is mostly about money, sex, life, relationships. There is rap like Eminem, and 50 cent, Drake. Some rap songs may have serious topics like love and life siutations but it can also contain just stuff about sex, ass (i.e. anaconda by nicki minaj) My personal favorite rap song is Stan by Eminem. I named a cat Stan after this song.
Lastly, country. There may be songs about tractors, farming, beer, love, sex and sometimes pain. There are different bands like Lady Antebellum, The band perry, even Lynyrd Skynyrd is considered country. I generally dont like country but my favorite country song is what hurts the most by the rascal flatts.
Every genre includes different things, different styles and instruments. Everyone has different tastes and some genres may be more serious than others. Five finger death punch is awesome but so is Beethoven in my opinion, along with the band perry and eminem. Some may like all genres, or whatever catches their attention and keeps ahold of it. Some may only like one genre. Music in general is amazing and serves an outlet, through emotions without needing to speak. Some songs can help you when you're sad, either by being sad (What hurts the most by rascal flatts) or being cheerful. Some may help when you're depressed and suicidal (coming down by five finger death punch) and some may just be nice when you're happy (like happy by pharell williams). Everyone has different likes when it comes to music and everyone enjoys music, but if someone doesn't then they have an outlet for them that music does for us. To some people, music is a controversial topic, assuming pop is shit or metal is about satan. Not necessarily true. People can like what they like and dont need to be judged for it. Music is something special a lot of people hold dearly to their heart.