This last point needs some clarification. Lojban Words Constructed languages create words in two main ways. There are some, mainly fictional languages like Elvish or Klingon, which make up all the words from scratch. Lojban falls half way between the two. This is one of the advantages of Lojban - it doesn't give a privileged position to European languages.
All root words have five letters.
Although these don't look much like any particular word in any language, you can see bits of different languages in each of them. This makes learning words easier for the largest number of people. There are 1,300 root words. This might sound like a lot, but it is nothing compared to the roughly 20,000 words a native speaker of a natural language knows. Lojban speakers have the freedom to create these compound words to express anything they want to say - if it catches on, it passes into the general Lojban vocabulary, and might even make it into the dictionary.