This the topmost “container” for content. The name can be appear within user friendly web addresses. So choose the names with care. You can create “blog” type formats that show articles in a tabular format
Every category lives within a section. Again the name can appear within user friendly web addresses. You can create blog type formats that use a tabular format.
These are where content lives. Every article is assigned to a category and section ( even if it is “uncategorised” ). Articles are only published when you decide it’s appropriate.
Most people start out creating articles in a standard desktop program - perhaps Microsoft Word. If you use this you should ensure you have filtered out the “Microsoft proprietary” HTML tags before pasting the content into the Article Editor. It can be easier to paste the content into Wordpad or Notepad, then save and then paste it onward - this has the same filtering affect. If you use the TinyMCE editor then the advanced option will show a "Paste From Word" button. Like any subject Joomla! has its own terminology - and ordinary English words may have particular meanings. If people don't understand the terminology they may fail to get the best from Joomla! - a real shame..
These determine the way the website appears - the colours, where things are on the page etc. Templates are normally constructed / bought when the website is created. It can be changed at will - so you may not need to change the content (in the articles) to change the appearance of the page. Most of this relies on Cascading Style Sheets and technical stuff - ask your advisor(s) if you’re interested.
Joomla templates are a series of rectangular boxes - each of which can contain content and have an unique name (template position). The exception is an article which normally is shown in the part of the screen not taken up by defined positions. e.g. the centre.
These exist completely independently of any page This gives considerable flexibility - there can be lots of menus. You can assign articles to one or more “menu items” at will.
This is where the name of the page ( that appears in the web address ) is chosen, and where the layout is selected ( e.g., Blog, article, wrapper ). Some Search Engine Friendly URL systems may allow alternatives to this.
A page layout that allows web pages from external websites to be included without change. This can be good (because it’s quick) and bad (because the look and feel may be very different).