Essentially its a salary in the twenty thousands if you're just a teacher.
The starting salary is £20,600 at the moment (outside of London). There's London weighting for fringes, outer and inner London, inner London is £25,000.
Going off the outside London teachers, they are on a payscale from £20,600 to £30,100.
You get more money if you get other responsibilities, head of department, head of year, responsibility for pastoral care or sections of the curriculum etc. Those positions have salaries of their own of a few thousand which go on top of your other pay.
Senior management get paid higher, possibly £40-50k for deputies, headteachers going up to £100k.
Headships pay well and its a goal of many teachers to get there however for job security it's like being a football manager, any slippages or problems with the schools performance and the LEA tend to have a quickfire approach to headteachers. I remember talking to a few of the teachers at my school about what they thought of it as a career and they said that they'd gone in hoping to end up as a head but when they'd seen what the head's job involved they were happy to stay out of it.
In comparison with other professions teaching is similar to other public services - police/fire service/ armed forces/ navy. Its going to be lower than lucrative private sector professions like finance and law. On the other hand the job security is better especially if you are a teacher of a shortage subject (Maths/Science/Modern Languages) and you get a good pension. The holidays are also obviously much longer than most others, out of 365 days in a year teachers work 195 days, 190 days the school is open and 5 training days.