static void Main(string[] args)
{
    // api key
    OsuClient client = new OsuClient("YOUR OSU API KEY");


    // user data
    OsuUser user = client.GetUsers(
        nameOrId: UserComponent.FromUserId(2) //or: new UserId(2)
    ).FirstOrDefault();
    
    OsuUser user2 = client.GetUsers(
        nameOrId: UserComponent.FromUserName("peppy"), //or: new UserName("peppy")
        gameMode: GameMode.Taiko
    ).FirstOrDefault();


    // beatmap data
    OsuBeatmap[] beatmaps = client.GetBeatmaps(
        beatmapSetId: new BeatmapSetId(3720)
    );

    OsuBeatmap beatmap = client.GetBeatmap(
        beatmapId: new BeatmapId("22423") // string is ok
    );

    OsuBeatmapSet beatmapSet = client.GetBeatmapSet(
        beatmapId: new BeatmapId(22423)
    );


    // score data
    OsuPlayScore score = client.GetScores(
        beatmapId: new BeatmapId(22423),
        nameOrId: UserComponent.FromUserId(2)
    ).OrderByDescending(k => k.Score).FirstOrDefault();

    OsuUserBest[] bestScores = client.GetUserBestScores(
        nameOrId: UserComponent.FromUserId(2)
    );

    OsuUserRecent[] recentScores = client.GetUserRecentScores(
        nameOrId: UserComponent.FromUserId(2)
    );


    // score extension method
    double acc1 = score.GetAccuracy(beatmap);
    double acc2 = bestScores.FirstOrDefault().GetAccuracy(beatmap);
    double acc3 = recentScores.FirstOrDefault().GetAccuracy(beatmap);


    // match data
    OsuMatch match = client.GetMatch(12345);


    // replay data (raw movements and clicks base64 string)
    OsuReplay replay = client.GetReplay(
        gameMode: GameMode.Standard,
        nameOrId: UserComponent.FromUserId(2),
        beatmapId: BeatmapComponent.FromMapId(22423) //or: new BeatmapId(22423)
    );
    

    // These classes will generate metadata like links or other information, and provide extensional methods.
    UserExtra userExtra = new UserExtra(user);
    Uri flagUri = userExtra.FlagUri;
    Uri ppPlusUri = userExtra.PpPlusUri;
    // ...

    BeatmapExtra beatmapExtra = new BeatmapExtra(beatmap);
    Uri setUri = beatmapExtra.BeatmapSetUri;
    Uri directUri = beatmapExtra.OsuDirectUri;
    Uri thumbnailUri = beatmapExtra.ThumbnailUri;
    // ...

    ReplayExtra replayExtra = new ReplayExtra(replay, score, beatmap); // Use this class to transform raw data from api to osr file.
    byte[] data = replayExtra.GetRawData();
    replayExtra.SaveOsrFile("D:\\replay.osr");
}