the iconic "I'm in my dreeeeeeeeeeeeeeeeeeEEEEEEEEEEEEEEAAAAAAAAAAAAAAAAAAM"

that high-note was a huge hit in Korea and she became very popular singer.

This song gave her the title as nations little sister, her iconic 3 high notes were attempted by like every idol ever lol. it gave her the popularity and the song was so different at the time that it created a huge impact, it even won song of the year. Good day was one of those songs, people would often try to sing in karaoke.

1. No, this was not her debut song. Her debut song was Mia. 2. The parrot in the beginning basically said "I love you, oppa" letting the cat out of the bag. That explains her defeated look after. 3. If we're talking about IU discography, this was THE song. It basically put her on the map and she has been consistently number 1 ever since.

IM IN MY DReeeeeeeeeeeeeeeEEEEEEEEEAAAAAAAAAAM ! "The nation little sister"

IU now 27 years old (international age), so 9 years ago, she was18 years old.

This song really blew her up. That legendary triple high note is everything. Up until now, you can still hear this song playing on the streets in SK.

This song made her to the top that she “defeat” popular idol songs back then. You can call this her “flagship” song. Good day was always on the charts #1 for how many weeks after its release. I’m not a music expert, but that high notes received many praises. As you can see IU’s original music style was this even her debut song (Lost Child). Her songs way back have really high notes (Don’t like her, Nagging, Every end of the day, Only I didn’t know etc..)

Good Day is the best IU's song I ever hear.

10:48 you are so cuteeee TT You should react to Ending Scene by IU too, you will love it!

This is the most iconic high note in kpop

She's really amazing soloist in kpop industry...this girl is on fire🔥🔥🔥🔥

the famous 3 hightnotes. classic iu songs

I've been a fan of IU since 2009 and this really sends me down the memory lane

It's was the song which made her as a top tier of Kpop and famous for the last 3 step high note.

this is still a hit song in Korea. for a decade 😍😍😍

I rewatch this reaction whenever I’m bored and I love it every time. Aaron’s growing smile is adorable and relatable lmao! Such a nostalgic classic.

The iconic three high notes 😍 Can't wait for you to watch her live performances of this song 💯 she still hits that high notes perfectly 👌take note, it's 100% live 😉

In her Palette song she sang 'but I did look beautiful in 'One fine Day' which is an alt title for 'Good Day'. She wore her rooftop dance dress in that video.

The song that shook a nation and forced everyone to pay attention to her talent

Please listen to The Red Shoes and Above the Time

This actually reminds me of classic kdramas and it feels kinda nostalgia

Been waiting for this, this is my favorite IU song of all time, that triple octave got me shookt the first time i heard it haha.

That high note always makes me smile

When IU sang good day, IU was in high school.

This is the song that blew her up to stardom. That iconic 3 high note is just wow.

Now it's time for Aaron to react to Good Day's live hahahaha please choose the ones that are kinda recent

This song live is more surprising You can see three high notes.

IU Queen of kpop 👑

IU used to have orchestra/theater-like songs up until You and I. Then she changed with 23. She didn't have much say with the songs/genre way back except with her acoustic covers. Plus if I'm not mistaken, she used to sing a lot of her songs in head tone.

I love IU’s current singing style too and she’s brilliant, but for sure, old/more newbie IU’s singing style is my fave.

For the lyrics, I really love IU's Knees and Unlucky. In 23, there's line "I never wrote even a single line of lies." so you will only find sincerity in her songs

this is song is gave her 1st major award.. Song of the Year Daesang Award in Melon Music Awards.. after she release Good day.. she became a top superstar soloist in korea..

that 3 steps high note is still one of an iconic untill now!! IU is the best!!

i hope u react to - Ending Scene - Love Poem - Knee - Through The Night / MMA performance - Dear Name

The guy that keeps recurring playing instruments in the video plays a supporting role the the drama "My Mister" that she starred in just before "Hotel del Luna." Also this is the song that made her a star.

After this you should definitely react to IU red shoes ... what a production

live is good too

As far as I know she was adviced to stop singing this because of the 3 key note change.

I'M IN MY DREEEEEEEEEEEEEAAAAAAAAAAAAM

Her high notes always so clear and comfortable to hear🥰🥰🥰

Can you watch IU Homebody Signal? She singing live and there's English subtitle... She sang a song that recommended by fans + She sang bts, baekhyun, etc song

This is my fav song from IU ever! TTTTTT

Can’t wait for you to react to more of her older songs they’re so amazing 😍😍

Im glad u finally react to the songgg.. this is my ultimate favourite song of IU

Yes thank you Aaron I've been waiting for this I'm in My dreaaaaaaaaaammmmmmmmmmm

얼굴이 참 매력적이예요 그리고 아이유 노래 들으면서 넘 행복해 보입니다 ㅎㅎㅎㅎㄹ

you should watch her singing live this high note live That is perfect!

yES THE ICONIC IM IN MY DREAAAAMMMMMMM

I will never tired to recommend you her debut song MIA, she start everything with that song, and honestly MIA, you and i, raindrop and good day are the song that i never removed from my playlist, and i still listen to that song up till now. You can also try the red shoes it also has a unique feeling . The story only i didn't know is good too but i rarely listen it, for me that song is too heartwrenching. Love poem, unlucky, the visitor, ending scene, is nice too And i will never tired to recommend you her live performance. You can start with her blueming performance from her love poem concert. And than you can watch her MMA 2017 performance its 180° different from her blueming performance but has the same power. If you already think iu's voice is good in her mv you will fall in love more when you listen to her live singing performance, and you can react to her 12 anniversary performance she worked really hard to prepare her 12th anniversary performance. She work almost for 14 hours and sing almost 60 song just for rehearsal for that day

아이유의 좋은 날을 만들어 준 좋은날ㅠ

Normally I don't comment much on youtube but I feel like I have to write whenever you post iu video. I'm getting happy, please continue 🌸

I SO LOVE THIS SONG OF IU IT ALWAYS GIVES ME THE NOSTALGIC HAPPY VIBE

YES!! good day is one of my favourites!😍😍

you also can watch the latest one sings by herself live with that 3 high notes!! at yoo hee yeol's sketcbook show ep 509. you should watch it, seriously.

This is literally one of her most iconic songs if not THE most iconic. I honestly haven’t listened to IU in YEARS! She is a legend

how can you not feel good whenever you listen to iu

You should react to "Ending scene" by her!!!!

reeeeally wanna see the red shoes TT

Placing her debut song Mia ( Lost Child) next to her shoot to fame song Good day is very much interesting. Personally, IU Mia debut song is more to my style :) Do check that out.

I think you should react IU sing this song in live performance... 😊

Queen IU🥰

I WAS WAITING FOR YOUR REACTION TO THIS ICONIC HIGHNOTES

IU voice is magical 💜

This song is so ICONIC

I never get bored with this song since 2011.

You should hear some of iu song in dream high (lots of jyp fam) too. It’s so good

This is a song every teenager can relate to, it's about puppy love, she loves the oppa, but he only sees her as a little kid.

didn't thought to click this so fast 😆😂

Your live performance is the same voice, your great voice...

omg u watched hotel del luna?!!! go watch moonlovers: scarlet heart too ITS VERY HEARTBREAKING but IU was so good in there. IT STILL HURTS mE.

Oh wow

Finally.....you would see various genres IU offered from her music journey ❤️ And I really like your patreon, I watched BTS, IU, and I-land contents there...I can't wait for your reaction to IU kdrama "My Mister" (I'm watching Hotel Del Luna rn) ❤️

Pleaaaseee watch iu's full performance in mma 2017 plssss

lol i subscribed to your patreon now because of hotel del luna hahaha thank u for mentioning it here on this video

OMG you saw my comment about you sounding like Owen Wilson 😆😂 this was a great reaction IU is truly amazing

I'm so proud of Queen 🥺

More IU. I hope you react to "Above the time" by IU too, the song and video is so nice, and the story...oh so good

React to Good Day Live in her 12th Anniversary Debut mini concert in Yoo Hee Yeol Sketchbook!

I love your reaction, so nice! IU has lots of good songs you can try such as The red shoes, Ending Scene, Dear name, Through the night, omg so many :))) And I hope you will react to the 2017 MMA performance of IU with the songs Through the night and Dear name. That was a legend performance.

Powerful vocal teenager IU

IU is my favourite singer. Her voice is soo beautiful and powerful

Thanks for u reaction...

I can't believe I missed this one I always follow and watch your iu reaction

I loved the way u were smirking throughout the video being proud.. 😂

😍🥰😘 love you aaron💜

Hahaha Finally I'm very curious your reaction when she sang the high note

react to the live performance of this ☺☺☺ try to compare 2010 vs 2020 live performance 😅

You should react to "Lost child", she was like 14 y.o there, and her vocals go crazy on that song.

I like your reactions :)

Aaron you should reaction live version of this song 🤭 she sing this song 3 weeks ago at channel KBS Kpop 👌🏻

*sees thumbnail* Me: FINALLLYYG good day is my favorite🤧🤧💜💜

i recommend 'Dear name' by IU, there's a live at MMA 2017 as well, dont miss it!

Please react to IU-friday

좋은 날 3단 고음 잊고있었는데 너무 좋다 ㅎㅎ

Please react to her live of good day on yoo heeyeol sketchbook 2020 and to her MV "Ending Scene"

3 OCTAVES FROM IU 👌🏻🔥😍 LIVE PERFORMANCE IS BETTER !!!!

Yess an iu reaction. Please react to her homebody signal or IUTV. Thanks!

Hey Aaron, TXT's comback is on Oct 26 and all the members individual teaser has already dropped. Please react to those!

Amazzinggg IU...