Sorcerer

Sorcerers are arcane spellcasters. Unlike mages, specialist mages or wild mages, Sorcerers don't prepare particular spells. Instead they are free to cast any combination of spells they know. However amount of spell Sorcerers know is very limited and they cannot learn spell from scrolls like mages instead they learn new spells, when they advance in levels.

Just like other arcane spellcasters they cannot use most of weapons, nor helmets or armors. Due to poor Thac0 and small amount of hit points they aren't very good melee combatants with weapons they are allowed to use either unless amplified with magic.

Sorcerer spells
Sorcerers are allowed to cast spells from 8 schools of magic. As Sorcerers are innate spellcasters they aren't allowed to copy spell from scrolls to spellbook.

Character abilities
While D&D sorcerers need charisma to cast spells in Baldur's Gate sorcerers can cast even 9 and 10 level spells with only 9 charisma.

Spell progression
Sorcerers with every gain both known spells and amount of spells they can cast. First table show progression of spells known by sorcerer and second progression of amount of spells available to sorcerer every day.