Uranium Backup is an industrial strength, and unusually configurable backup tool.
You don't have to get into its complexities immediately (or at all), if you don't want to. Point and click to specify a backup folder or two, choose a destination (a local, external or network drive), one more click and the program will copy your selected files - it's all very straightforward.
If you need more power, though, there's plenty available in the Options dialog. The Direct Copy page, for instance, lets you define when files will be overwritten: options include always, if the destination file is older than the source, smaller than the source, older and smaller than the source, older or smaller than the source, or different from the source (there are 3 comparison methods on offer). You can choose to copy the source files dependent on their date or size, and there are options to copy the NTFS security attributes of your files (or not).
And the scheduler is almost as flexible. You can run particular jobs on particular times and days of the week; on selected days of the month; at a defined interval in days, hours or minutes, or on a specific date and time. And you can prevent the backup running until a file exists, with a particular size or date, or even includes the text you specify.
Again, it's not compulsory to get into any of this, so don't be put off by the apparent complexity. But if occasionally you need some extra backup power then Uranium may be able to help.
Please note, this free version of Uranium Backup does also have some limitations. It can't create disk images; it can't back up to FTP servers, synchronise folders, be run as a service, or create ZIP files bigger than 4GB, and you don't get technical support.
Other versions remove these limitations, and add other features: email backup, SQL Server backup, Volume Shadow Copy support, backup to tapes or optical drives, and more. Prices start at 80 Euros, and you can find out more on the Uranium Backup site.
Uranium Backup Free has a lot of power, but some of the limitations - like a 4GB maximum on its ZIP files - may be a problem