Update 2022: This software no longer exists.
Multi-Language word memorizer is a free software to memorize words of different languages. It is not a complete language learning software, as it does not focuses on phrases. Instead, it helps you memorize commonly used words of international language. Once you get a hang of some commonly used words, you can move on to complete language learning with other free language learning software.
This free language learning tool is quite easy to use. You start with selecting your native language, and the language you want to learn. Then you select the list of words that you want to memorize. Memorizer will then randomly show you words from that list, and you will need to identify what does that word means. Some regular practice with this will make you learn many words of language of your choice.
You can add or remove words in this language learning tool. Apart from that, you can choose words category like simple words and verbs. You can use timer for memorizing words, and even add languages to this free words memorizer.
Words Memorizer is completely free and open source. If you are a software developer, you can even download the source code and play around with it. Another free language learning software includes Busuu.