1. OBS Studio

If you're a gamer, OBS Studio is without a doubt the best free screen recorder available. Unlike the widely used FRAPS (which only allows you to record for 30 seconds at a time unless you purchase a licence and adds a watermark to the resulting footage), OBS Studio is open source and completely free to use.

OBS Studio supports high-definition streaming and recording, with no limits on the number or length of your creations. You can stream live gaming to Twitch or YouTube, save projects for later use, or encode your footage in FLV format and save it locally.

Because OBS Studio records directly from your graphics card, it can capture games in full-screen mode (many other screen recorders can only record if the game is windowed), and you can control the recording with customizable hotkeys. OBS Studio can also take advantage of multi-core CPUs for better performance and record at 60 frames per second (or even higher).

OBS Studio is by far the best and most powerful screen recorder for gamers. It may take a little time to get it set up exactly how you want it, but it is well worth the time.

2. Screencast-O-Matic

Screencast-O-Matic is yet another free browser-based screen recorder, and one that is quite capable. You can record as many clips as you want, zoom while recording, trim your recorded clips, add captions, save them to your desktop, YouTube, or the cloud, share a video link, or add one of 30 royalty-free music tracks.

Press 'Start free recording', then 'Launch free recorder.' You'll be prompted to download and install a small web launcher, just like with Apowersoft Free Online Screen Recorder, before the screen recorder will start recording. Prepare your screen by adjusting the size of the recording window to your needs (it can record the entire screen or just a portion of it), then press the red button. You can record footage from your screen, a webcam, or both, and capture audio from your PC or a microphone.

Upgrade to a Deluxe account for additional features such as scripted recordings, drawing and annotations, a video editor, and (perhaps most importantly) the ability to automatically generate captions with text-to-speech. For $1.65 (approximately £1, AU$2.50) per month, that's an impressive set of tools, but Screencast-O-free Matic's version has a lot to offer as well.

The only real drawback is that unless you upgrade, your recordings will be watermarked, but if that's not an issue, this free screen recorder is well worth a look.