Subdomain: It is an addition to your subdomain. For e.g.: You can create subdomain for you website blog like blog.yourdomain.com.
Addon Domain: Some host have options to add multiple individual domains to the single host. This can be achieved using Addon domains in the Host control panel. Once Addon domain for a particular domain has created, Nameservers of the host should be added in the corresponding Domain control panel.
Host or Webhost: It is the storage which contains your website files. It is a server which hold all the files related to your website. Some of the well know website hosts are www.bluehost.com , www.hostgator.com .
Domain Mapping: It is the way by which you link your domain name to the corresponding host. It can be achieved by means of Nameservers.
Nameservers: These are the IP address meant for you domain provided by the host when you purchased the host. This has to be implemented in the domain control panel. Usually Nameservers will look like ns1.domainname.com, ns1.domainname.com etc...
Domain control panel: It is the backend of your domain. Which have options for entering Nameservers, MX records, CName etc. You will get access to your domain panel once you register your domain with the domain registrar.
Host control Panel: it is the back end of your domain host. Which consist of file manager where we have to upload your website files. It also has access to PHPMYADMIN, MX records, Subdomain, Addon domain, etc… Some popular control panels are Cpanel, Plesk.
MX records: It is also called mail server records. It is something given when you use third party mail service for your domain like gmail, outlook etc. It has to be added in the MX record of your Domain control panel or Host control panel to send and receive emails.
CMS: Content Management System or CMS is the platform to publish your website. It has to be installed in your webhost. Website contents can be add from the CMS backend. Well know CMS platforms are WordPress, Joomla and Drupal.
Bandwidth: It is the amount of data allowed to transfer in a particular period of time for a domain. For e.g. 1 gb per months means only 1 gb of your website data is allowed to transfer from your host.