1in addition to something else that you have mentioned:
Information is also available on women's health care.
She sings beautifullyand alsoplays the flute and piano.
The system was not onlycomplicated but alsoineffective.
2used to say that the same thing is true about another person or thing:
My girlfriend was also called Helen.
WORD CHOICE: WORD CHOICE: also, too, as well, eitheralso, too and as well can be used in many of the same contexts• She's a valued colleague, and a great friend too OR and a great friend as well OR and also a great friend.also is the most formal and the most likely to be used in formal writing such as reports.as wellis the most informal and the most likely to be used in speech.!! too is never used at the beginning of a clause. Alsois not usually used at the end of a clause• Smoking makes you ill. It costs a lot too/as well OR It's also expensive OR Also, it's expensive.Use eitherwhen you are adding another negative fact• Our first attempt didn't work, and our second didn't either (NOT also didn't).
Definition from the Longman Dictionary of Contemporary English Advanced Learner's Dictionary.