Oh my, where to start. Ok
Server: the computer on a network that supplies all the other computers with their log in information (the head honcho). It could supply the Internet connection as was previously suggested. That would make it an Internet Service Provider or ISP. It could also supply login information or applications that the client computers use.
Browser: A program that allowes a computer to surf the Internet. It could be Microsoft as is in the case of Internet Explorer. But there is also Netscape Navigator or Mozilla and about a hundred others to choose from.
URL: was already defined.
You can read some attachments and not others probably because of your virus protection or your email program settings. Some attachments can and often are viruses so your virus protection will block them. Jpegs are picture files and generally are harmless. An EXE file or VBS file can and most likely is a virus so if you open it, it executes a program into your computer and Bye bye hard drive (the main storage facility on your computer).
Hope this helps.
