Check out example codes for "dequeuereusableheaderfooterview". It will help you in understanding the concepts better.

Code Example 1

- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
{
    return 40.0;
}
- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
{
    static NSString *headerReuseIdentifier = @"TableViewSectionHeaderViewIdentifier";

   // Reuse the instance that was created in viewDidLoad, or make a new one if not enough.
    UITableViewHeaderFooterView *sectionHeaderView = [tableView dequeueReusableHeaderFooterViewWithIdentifier:headerReuseIdentifier];
    sectionHeaderView.textLabel.text = @"Non subclassed header";

    return sectionHeaderView;

}

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