|Incidentally.. if that toolbar arrive on its own as it were - you didn't deliberately install it... then likely it arrived some other software/utils etc. you installed via a download off the web.|
Almost all third-party apps/software/utils etc now includes a whole slew of stuff you neither want nor need. Using the default "automatic" installation option guarantees you "will" install a lot you don't know about; and is PAI to eradicate at times.
Using the manual/custom option allows "you" to see what is pre-checked for installation, and then uncheck it. Thus ensuring you install "only" what "you" want installed - usually of course the actual app etc. only.