If you are interested in learning how to make beats make sure you are not using an online beat maker.
Using online beat makers is not a wise thing to do. No even half-hearted hip hop beat producer will touch any online beat program. There are many reasons for this, the primary reason being lack of sound quality. Most online beat machines produce MP3 sound files, these are not nearly good enough quality to be used for anything other than ringtones.
If you ever plan on selling your beats or trying to get signed it is absolutely imperative that you are producing broadcast quality beats. No radio station or big artist will even consider touching your 1 bar beat that was mastered as a second generation MP3 mixdownit would even be a stretch saying someone would want to use at is a ringtone this day and age.
Also, to use an online beat maker you have to have a crazy fast internet connection or there is no way you will be able to maintain a consistent flow and loop.
Assuming you do produce a track online, you wont be able to play it on a loud system. It will just buzz and crack and sound more like static than anything.
Not to mention the fact that I dont think anyone, no matter how good they are can produce anything worth listening to on one bar looped. That shouldnt even count as a beat maker, it should just be called a looper.
Just do yourself a favor and dont try to cut corners. If you try to use an online beat maker you will just be wasting your time and money. Do it right from the beginning, download a quality beat software that produces broadcast quality 44.1 16BIT stereo .wav files and start laying down professional tracks.