How to Learn to Code in 2023

Ғылым және технология

This video is a comprehensive breakdown of the strategies you’ll need to learn to code and be a self-taught software developer.
🏆 * Coaching Program *
Interested in joining my paid coaching program and getting support to get your software development career started? If you consider yourself an action-taker, you're ready to invest in your career and you're committed to putting in the work then book your intake call at andysterkowitz.link/call-00080
📚 Books Recommended In The Video
* HeadFirst Javascript amzn.to/3CxoQjK
** Disclaimer **
I'm a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon properties including, but not limited to, amazon.com. Amazon offers a small commission on products sold through their affiliate links. Each of your purchases via my Amazon affiliation links above supports my cause at no additional cost to you.

Пікірлер: 122

  • @AndySterkowitz
    @AndySterkowitz Жыл бұрын

    Now that we're in the new year where are you at with "learning to code"? I am trying to get a gauge on where my audience is at for future videos. Please let me know know ✌️

  • @songlore4617

    @songlore4617

    Жыл бұрын

    I'm doing the meta android development certification program. Learning kotlin and considering at least learning to read java since it's possible what I'll be working on will be an old codebase. I've also noticed from what I've seen of Java that it helps give me a better understanding of Kotlin. There are a few different meta certifications so I did several of those courses as well. They each have a final project to complete where I actually learn the language/concepts taught.

  • @pastorsrule

    @pastorsrule

    Жыл бұрын

    I'm still learning the basics of Python and now Javascript. I'm 4 months in, but struggling to assimilate difficult concepts into a single project. I keep going over the same videos in my Udemy courses because I'm not really grasping what I'm being taught (i.e. classes). So I'm struggling! But I feel encouraged by your videos. Thank you so much Andy.

  • @pastorsrule

    @pastorsrule

    Жыл бұрын

    Forgot to mention, I'm a 32 year old who wants to switch careers mid-stream with no software developer experience

  • @samueleneh714

    @samueleneh714

    11 ай бұрын

    Can I be your student..😢plz

  • @luistovar6916
    @luistovar6916 Жыл бұрын

    I'm an Android developer and I've been watching your videos for a long time in order to improve my English and thanks to them I've got an offer from a foreign company

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    Congrats!

  • @MiguelAngelBenitezYanez

    @MiguelAngelBenitezYanez

    Жыл бұрын

    Yo ando en el mismo modo. ¡Sí podemos!

  • @luistovar6916

    @luistovar6916

    Жыл бұрын

    @@MiguelAngelBenitezYanez si se puede, solo es cuestión de tiempo

  • @HrissW

    @HrissW

    Жыл бұрын

    @@luistovar6916 is your speaking lev is c1? Does companies ask for fluent speaker

  • @luistovar6916

    @luistovar6916

    Жыл бұрын

    @@HrissW I think my level is almost B2, I applied in different companies, mainly to practice my English and to know what I had to improve, and I started getting better on my speaking. For somoe companies it was enough and they let me continue the procces but for others my level needed to be better, like C1, so as Andy said it is a good idea to start applying even if you dont feel ready

  • @panawafful
    @panawafful Жыл бұрын

    I'm so happy you made this video! I've felt pretty hesitant about which direction to go for programming and I'm sure that's stopped me from committing to it, but I appreciate how straightforward and simple this is. Definitely going to start my journey this year!

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    Best of luck!

  • @SendaPlays
    @SendaPlays Жыл бұрын

    A month and a half in so far, I get unemployed at the end of February and now is my time to change careers so my motivation is strong. Just finished the jQuery module and looking forward to touch some BackEnd! Thanks for the videos, much appreciated!

  • @AleksandarAndric-uo2gg
    @AleksandarAndric-uo2gg Жыл бұрын

    Well i am 35 years old and plan to start JavaScript learning. I already found and downloaded Head First JS book (before this video) and will follow your advices. I will post updates from time to time to let you now how my progress is going. Wish me luck guys.

  • @dnasredine
    @dnasredine Жыл бұрын

    I really appreciate the clear and straightforward approach you have taken in explaining the steps for learning programming and securing a job in 2023. Your explanation has been easy to follow, and I feel more confident in my ability to take on this task. The details you have provided have been extremely useful and I can not wait to get started.

  • @PoloGonoaa
    @PoloGonoaa Жыл бұрын

    I’m now C++ in my university but I’ll switch it web development and use programming knowledge I acquired in C++ to learn backend language like Python, JavaScript or Java. I’m a big fan of you Andy. I downloaded your self study manual. Once again, thank you so much Andy ❤️🙏

  • @yuriish7570
    @yuriish7570 Жыл бұрын

    very reasonable steps and advice. Thanks for clarifying

  • @redeagle9312
    @redeagle9312 Жыл бұрын

    Andy, thanks a lot again. Your insight guide is my compass. I really appreciated.

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    My pleasure!

  • @fausatbakare9773
    @fausatbakare9773 Жыл бұрын

    As a beginner, I found this so encouraging and informative. Thanks so much 👍

  • @alexandranesterenko
    @alexandranesterenko Жыл бұрын

    Very inspirational, thank you! Going to learn Java for backend.

  • @calebe1017
    @calebe1017 Жыл бұрын

    I enjoy so much the ideia of count hours not about the day, but the week ! That's really a great way to measure some development!

  • @davidkozak4507
    @davidkozak4507 Жыл бұрын

    I'm just getting started and after watching a few of your videos along with some other searching, I decided to start by learning Python. Then going and learning JavaScript or PHP in a few months after working on a few projects with Python. I chose to start with Python because it seems like that would be more relevant for back end (which is what I'm looking to get into). a video on back end vs front end or what kind of environments different specific careers operate in would be cool!

  • @frankcastellanos
    @frankcastellanos Жыл бұрын

    This video advice is the best

  • @alexandervaladez4059
    @alexandervaladez4059 Жыл бұрын

    thanks for the steps, i have been wanting to do code for a long time I am a car tech now but i really still want to switch careers, thank you for a point to point run down on how

  • @Wrobi3
    @Wrobi3 Жыл бұрын

    Great info. Thank you!

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    Glad it was helpful!

  • @brittanyhurt-head9087
    @brittanyhurt-head9087 Жыл бұрын

    I am currently working as a revenue analyst. I made the decision to commit to changing careers to become a web developer 2 months ago. I started off my journey wanting to be a full stack developer and enrolled in a bootcamp. JavaScript is my nemesis currently. I want to master this language before making a concrete decision. I actually just purchased the book on JavaScript you suggested

  • @isatheone
    @isatheone Жыл бұрын

    I’ve always been curious about software development and how it works to become the final product I’ve also always had an interest in problem solving and organisation I only really know the basics of computer functions but I’m so excited to fill in more of my knowledge this year and get started learning coding!

  • @jreed150483
    @jreed150483 Жыл бұрын

    Hi Andy, I have had aclear goal which is Front -end web development really love it. Started this Journey Jan 22 knew nothing but have learnt so much. Leart HTML and CSS now learning Javscript which i still find challenging. Currently doing Front end career path on Scrimba. My goal this year is to really understand and get to grips with Javascript. I have Full time job, family and commitments but still try to find time at least 2 hours a day to lean and code. Desperate to change career and do something i am reallly interested in. Front-End i love. Also turning 40 this year but still motivated to acheieve my long term goal which is change career and become a front-end dev. Hope i can get there. Thanks for this video gives me motivation

  • @Ati-kx5sh
    @Ati-kx5sh Жыл бұрын

    Just starting out my programming journey. I’ve graduated high school a week ago. As for now I’ll try to take everything slow.

  • @nathancastaneda2657
    @nathancastaneda2657 Жыл бұрын

    Today is my starting day. Well I’m still gathering but I’m starting to learn today:)

  • @ChristianZelada98
    @ChristianZelada98 Жыл бұрын

    Hey Andy, just started to learn code about a week ago. Currently also as a car salesman. Ready for the process ahead of me

  • @usamahussain4461
    @usamahussain4461 Жыл бұрын

    Hey Andy. Always good to hear from you. 1 question: How can one develop this skill "Thinking like a Programmer"? Books, courses or just building projects and solving problems?

  • @techmentormaria
    @techmentormaria Жыл бұрын

    The one thing that I learned after being in tech for more than 13 years is that you never really stop learning. There is always a new language or framework to explore and you can never just do the same technology forever. (Thank god)

  • @VeretenoVids
    @VeretenoVids Жыл бұрын

    I got started gung ho about a year ago and then life got in the way. I'm in a place where I can get back to it, but stuck on deciding where to start--go all the way back to zero or trust that I've still got some knowledge rattling around in my brain and jump to "advanced beginner". So, yes, I'm at stage waffle.

  • @allybiggs5423
    @allybiggs5423 Жыл бұрын

    Fantastic video I'm thinking of making the transition into coding. My background is IT technical stuff like Linux and Windows in a helpdesk environment.

  • @mps_unltd
    @mps_unltd Жыл бұрын

    2 years in and I'm still teaching myself to code basic HTML/CSS. I dont have the money or time for a Bootcamp or College. I dont even know anyone that is a Web Dev to help me so KZread tutorials are my only option. It's really tough. Right now I'm stuck on a Web design project trying to get Font Awesome icons to work and cant figure out why they wont. They work on everything else but this project. So frustrating. I'm marking this one (Broken) and moving on to a different project. Maybe I will have better luck with that one. I keep pushing on. Eventually (some day) I will get good at this. If I'm lucky maybe I will land a Dev job in 10 years. LOL.

  • @anthonyhaga7559
    @anthonyhaga7559 Жыл бұрын

    I’m still in the later end of the basics. I’ve gotten to the point where learning more concepts day to day doesn’t really help me, because I need a way to practice them. On the other hand, I’m not sure how to “practice” coding. Unless just writing for loops and such repeatedly counts. Love the channel, here’s hoping everyone can learn to code this year, including myself. Cheers

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    Build projects! ;-)

  • @DevlogBill
    @DevlogBill Жыл бұрын

    Learning Django with Python for backend. Last year focused on JavaScript as deeply as possible. But once in a while I will go back to the basics and focus only on HTML and CSS and create a basic static site. Thanks for the video.

  • @juanzamarripa3133
    @juanzamarripa3133 Жыл бұрын

    I still haven’t started but I’m watching videos to prep. I want to freelance my skill,

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    Best of luck this year. Let's get you started ASAP.

  • @chrisjunior91
    @chrisjunior91 Жыл бұрын

    i've been on and off learning for a year now. life happens unfortunately. however you are 100% right on narrowing down what you want to do. i kept watching videos that say do this and do that, an i was all over the place learning languages i'm most likely never going to use. i've been heavy on python 3 even though i started with html i skipped css and javascript. At this point i feel overwhelmed and i don't even know what i want to do. i have completed 3 simple python projects already and i think i should just put all my effort into understanding python all the way.

  • @hellsp4wn243
    @hellsp4wn243 Жыл бұрын

    I've learned a bit of HTMl, CSS and JavaScript, built a very small and simple portfolio, after this video looking for intermediate projects and an advanced one

  • @duymai1747
    @duymai1747 Жыл бұрын

    You have a really nice voice!

  • @mrmiagi6052
    @mrmiagi6052 Жыл бұрын

    ive been self studying full stack web development for just shy of 2 years. ive created one full stack project as well as a bunch of front end projects. i have a bit of experience in react. I have my portfolio set up linked to a resume, and now I am griding leetcode problems realizing i need a bit of work on my javascript but i really need to land a job soon. I actually havent applied yet

  • @MattSobek
    @MattSobek Жыл бұрын

    I just finished my BS in Software Development in November and I think I'm hardcore in the "imposter syndrome" phase. I got laid off in October so finding a job is definitely high priority. But I appreciate this video. I think it gave me a little motivation to get past my fear.

  • @chewyvex3223
    @chewyvex3223 Жыл бұрын

    Been following you and watching your content for almost a year good sir, finally had my first interview as an e-commerce web developer after building a few portfolio projects. They will be assessing my coding skills this week. Do you think LeetCode or Hackerrank will help? Or do you recommend another way for sharpening coding skills?

  • @MrBattlekiwi
    @MrBattlekiwi Жыл бұрын

    Hey, thanks for the very informative video! I started learning about a month and a half ago, and I've finished everything i think I can learn from the course I was taking just didn't know where to go next. I have a set of projects from the course, though those were heavily guided so I don't really think those count for too much. What I think I struggle on now is just kinda thinking like a programmer or like figuring out where to start with a project, trying to go into software development at the moment and maybe game development if the opportunity arises in the future. I've only been learning javascript so far, but I guess my question would be do you or anyone else in the comments have any good examples of one of the big capstone projects for software development specifically?

  • @hotplotsandsynonyms
    @hotplotsandsynonyms Жыл бұрын

    Thanks for the overview, Andy! I keep a lot of your videos playing in the background of my day job to get my thinking about my coding when I have time in the evening. It's been really helpful! I'm starting a scheduled, dedicated study over the next 6 months to work towards full stack development, starting in Python because my day job offered a free training course in it last year so it's the language I know best. I'm in the phase of making simple projects to build skills, learning the Flask framework for Python so I can do full stack development. Pretty close to moving into intermediate projects. Question: If I learn Python and at least one of it's popular web frameworks, should I still learn Javascript before applying, or let that be something I learn on/slightly before the job?

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    Awesome! You can learn Python first...nothing wrong with that. You will want to learn JS before applying for jobs though.

  • @hotplotsandsynonyms

    @hotplotsandsynonyms

    Жыл бұрын

    @@AndySterkowitz Thanks! I've dabbled in JavaScript and quickly learned that it was a terrible idea to try and learn two languages at once, but I can add JS into my study add it in once I'm more comfortable in Python.

  • @AndresSanche23
    @AndresSanche23 Жыл бұрын

    I've been on and off learning to code with some python experience on a Lewagoon Data Science Bootcamp. I haven't got a job offer now. I work in finance (NOT PROGRAMMING AT ANY LEVEL) . But I feel I need just a little push to see what language is for me. I really like data and doing new projects, but I feel like python is extremely broad.

  • @bortbreadface6259
    @bortbreadface6259 Жыл бұрын

    I'm ready to start applying actually, (although I'm still finishing up a couple clients / projects). I went through 100Devs. Don't suppose you're hiring or have any leads on the West Coast of Canada ? 😅

  • @udayanuu7180
    @udayanuu7180 Жыл бұрын

    What do you have to say about the path that I have chosen which is c followed by c++ followed by c#

  • @justinjeffries1554
    @justinjeffries1554 Жыл бұрын

    I literally started today with Harvard's CS50x. Programmed my first thing on Scratch. Messing around with making a itty bitty game on there. The course is free

  • @GamingUnitesGR
    @GamingUnitesGR Жыл бұрын

    Can you make a walkthrough on building a portfolio for a software dev?

  • @mdelim3128
    @mdelim3128 Жыл бұрын

    Andy I'm working as a chef professionally but wanted to change career as software developer I tried studying java again but in the past I self studied c++,but then again because of life I need to work as a chef for the meantime to earn money but I do actually want to change careee this new 2023

  • @BlvckBoyGreg
    @BlvckBoyGreg Жыл бұрын

    Hi, I’m Gregory. I’m a FullStack Developer but I haven’t fully grasp my BackEnd Skills yet because I need some guidance. I tend to better on my FrontEnd Skills. What do you think I should do because I want to be able to do some BackEnd work too. Thank you.

  • @stevecrabtree9141
    @stevecrabtree9141 Жыл бұрын

    Kind of going down the tutorial hell pathway 😏 it's pretty tough branching out on your own, but have started...

  • @Henriflute
    @Henriflute11 ай бұрын

    Man, would it be better to just go for Java or C# directly or it would be wiser to learn JS first and then later on expand to java/c# languages too?

  • @antotot04
    @antotot04 Жыл бұрын

    would you reccomend CS50 as a source to start learining coding?

  • @pabloandrescaceresserrano263
    @pabloandrescaceresserrano263 Жыл бұрын

    I'm struggling with Deep Learning right now. I admire those guys who can write code as they write a letter for mom. It is so tricky to try to retain instructions, norms, tips & tricks, code arguments, syntaxis rules, etc. I'm a psychologist, so the learning curve I must cope with is steeped

  • @royalrockets6041
    @royalrockets6041 Жыл бұрын

    Only subscribed because of the way he through that I there

  • @lamename2518
    @lamename2518 Жыл бұрын

    I keep forgetting I finish multiple courses and at the end I feel like I can't do anything right now I am studying for the 10 time from different course every time javascript, I learn something new every time though but I hope this time I'll be ready

  • @anshsrivastava61
    @anshsrivastava61 Жыл бұрын

    Can you tell me what is the role of data structures and algorithms in frontend development. i am Nobie

  • @sublitt
    @sublitt Жыл бұрын

    I started my journey a little over a month ago and I'm stuck on the starting the first projects area. I've learned most of Python and in the process of learning Javascript with some SQL/C++/C. I've gone over multiple tutorials but every time I see that blank screen I just seem to not know where to start.

  • @dtoplife9374
    @dtoplife9374 Жыл бұрын

    What is your opinion on code academy

  • @royalrockets6041
    @royalrockets6041 Жыл бұрын

    Wow my mans made is feel so simple

  • @adamdmi5752
    @adamdmi575210 ай бұрын

    Cybersec engineer, going for more into devsecops. Just chasing the dreams, and want to be sre one day... :) ❤

  • @programmer9428
    @programmer9428 Жыл бұрын

    back in 2021 you have a video about how to become a programmer and i watch your video and more videos and i love it and it helps me to motivate but sometimes the reality of how to become a programmer is so boring because you need to learn a lot and now 2023 i stuck of what language should i pursue to focus like java, python, c#, JavaScrip, what is your advice? 😪 im struggling now. shss.

  • @BRad-mu6qr
    @BRad-mu6qr Жыл бұрын

    I’m trying to change my career from being a janitor to a web developer or a app developer

  • @Bilal_1860
    @Bilal_1860 Жыл бұрын

    Andy what do you think about chatgpt bro?

  • @valceri3151
    @valceri315111 ай бұрын

    Is Head First JavaScript Programming good for learning js in 2023?

  • @trevorsmith3475
    @trevorsmith3475 Жыл бұрын

    Do you write codes for people

  • @taiquangong9912
    @taiquangong9912 Жыл бұрын

    Im learning Python for cybersecurity.

  • @PapaPaprikash
    @PapaPaprikash Жыл бұрын

    Are those 7 projects for the first month? Or is that the goal for the year?

  • @siman211
    @siman211 Жыл бұрын

    Anyone knows a good udemy course for fullstack web dev? Just please don't give the one of Andrei Neagoie, don't know if is too hard for me but I did not understand almost nothing from it, instead it kinda made me hate html/css.At section 12 of the course it made me fell that my knowledge was going to negative

  • @mr_don_key
    @mr_don_key Жыл бұрын

    portfolio's aren't needed per sé, often times you get an assignment to do (either on the spot, or at home)

  • @mbreinl3980
    @mbreinl3980 Жыл бұрын

    Hello sir could you please create for my a small Tools ?? If you could that please let me know

  • @michaelbarasa6886
    @michaelbarasa6886 Жыл бұрын

    Am a graduate software engineer from Kenya Bsc software engineering and since i graduated 2021..am struggling to find a job.i learnt java,and c programming back in school. i shifted to JavaScript and react framework from August last year (self learning). i just need your help.

  • @israelojehonmon-nf6ql
    @israelojehonmon-nf6ql Жыл бұрын

    I started with html & css

  • @besthobbit
    @besthobbit Жыл бұрын

    Idk if I can do 15 hours a week but I'm doing my best.

  • @25sumpter
    @25sumpter Жыл бұрын

    Hey Andy I am looking at codecademy career paths in your opinion is it worth it?

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    I'm honestly not sure...I'm not familiar with it at all.

  • @25sumpter

    @25sumpter

    Жыл бұрын

    @@AndySterkowitz thank you for responding

  • @meeknkosi

    @meeknkosi

    Жыл бұрын

    I dont think they are worth it at all

  • @25sumpter

    @25sumpter

    Жыл бұрын

    @@meeknkosi why not?

  • @meeknkosi

    @meeknkosi

    Жыл бұрын

    It did not gv me that zeal to learn !

  • @musababdulmalek8949
    @musababdulmalek8949 Жыл бұрын

    I am now learning Python, I already cover the basic in term of concept but struggle on thinking of project. My aim was to be game developer so I know python is not language for it. I am learning so I have easier time on concept. I not really enjoying doing python as I like I going opposite direction where headed to. So, should I remain with python or go to C++ or C#? I know game developer is lot harder to get into so I still kinda want to stick with python. Hope anyone here can help 😀

  • @kaoriii2763

    @kaoriii2763

    Жыл бұрын

    Try c++

  • @rahalmehdiabdelaziz8121
    @rahalmehdiabdelaziz8121 Жыл бұрын

    I have a very important question: How learning software dev will change after Chatgpt and the explosion of the AI ???

  • @Poifix
    @Poifix Жыл бұрын

    I've always wanted learn coding. It always seemed like a fun skill to have. Sometimes you sit and need something, some app or a website. And you wonder why this is not a thing that exists. So you wish you knew how to do it yourself. I've been trying to learn web developement the last 67days. HTML went pretty well, however CSS and JS just doesn't click with me. in CSS I can't make anything look good. And positioning stuff and animations is the bain of my existence. And when it comes to JS I don't know how I am suppose to create anything functional out of all these "make no sense" calculations, for loops, while loops etc. I literally don't understand and it takes the joy away from learning any more.

  • @cwinter90
    @cwinter90 Жыл бұрын

    Step One: Buy a sit/stand desk, two 49" super ultra wide monitors, ergonomic keyboard, ergonomic mouse, and ergonomic chair. 🤣 Step two: Sit down and let the imposter syndrome take over. Only this time... It's justified because you don't know squat yet. Step Three: Learn something useful at a 10x rate you normally would because you're comfy and have sooo much screen space. Step Four: $$$$ 😁 Obviously a joke but a space free from distractions and that you're comfortable in is definitely a must.

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    Lol

  • @bl1ngy628
    @bl1ngy628 Жыл бұрын

    I just got a job as a Junior Software Engineer and I feel like a big impostor since I come from the Networking and Cybersecurity field 🤦‍♂️

  • @sandeeptanjore1253
    @sandeeptanjore1253 Жыл бұрын

    Just getting stuck in this tutorial hell. Feel bad about it. In fact just cannot wrap my head around CSS.

  • @Mitchyugan
    @Mitchyugan Жыл бұрын

    I am a frontend developer looking for a job

  • @thepuppetqueen57
    @thepuppetqueen57 Жыл бұрын

    I just like to say I am a python dev and no I am not planning on getting a job

  • @lineCooking101
    @lineCooking101 Жыл бұрын

    I’m getting close to applying for jobs, but chatgpt has me thinking 50% of them will be gone in 5 years

  • @justinbeee369
    @justinbeee369 Жыл бұрын

    Hmu

  • @manuelgonzales6483
    @manuelgonzales6483 Жыл бұрын

    FIRST 🥇🏆😍

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    You win!

  • @manuelgonzales6483

    @manuelgonzales6483

    Жыл бұрын

    @@AndySterkowitz Im working on COBOL right now. What do you think?

  • @cwinter90

    @cwinter90

    Жыл бұрын

    @@manuelgonzales6483 🤣

  • @manuelgonzales6483

    @manuelgonzales6483

    Жыл бұрын

    @@cwinter90 🙄

  • @Username8281
    @Username8281 Жыл бұрын

    Hey

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    Hi

  • @siman211
    @siman211 Жыл бұрын

    Is red? my button is black

  • @khalidnosirov6979
    @khalidnosirov6979 Жыл бұрын

    Would be great if you shared your opinion about chatGPT.

  • @BaymaxIsBig
    @BaymaxIsBig Жыл бұрын

    What about freecodecamp videos on KZread, would that help ?

  • @AndySterkowitz

    @AndySterkowitz

    Жыл бұрын

    100%

Келесі