You can open several files in tabs from the command line with vim, just type:
vim -p file1 file2 file3
And each file specified on the command line will be opened in a new tab.
To open a file in a new tab inside vim use :tabe file
To close a tab do :tabc
You can quickly switch between tabs typing gt or gT in normal mode. To switch to a particular tab prepend the tab number to gt, i.e. type #gt, where #gt is the tab number.