All zone one day travelcard: Cannot be bought on the bus. Buy on the day from Underground or Railway stations within Greater London. Can also be bought at Network South East Railway stations as an 'add-on' to a return to London, generally at about £2.30 above the cost of the usual return fare to Zone 1. Now available in Peak and Off Peak versions on Mon-Fri: Peak valid from 0001 on day of validity, Off Peak version from 0930. Both then valid until any journey commencing before 0430 the following morning. On Saturdays and Sundays Off-Peak version is valid all day, so Peak version only necessary Mon-Fri. Peak One day: £10.50 (Child £5.20), Off Peak £5 Adult (up 10p), £2 Child (No change).
Valid on: All London Underground lines (except North of Moor Park on the Metropolitan line), Docklands Light Railway, Croydon Tramlink and National Rail services within Greater London. All Buses in Greater London which display the 'London Transport Bus Service' sign, including Express 726, and LT N-Prefixed Night buses for journeys which commence anytime before 4.30am on the morning following expiry.
Also valid on: Services from Outside that go in: Most non London transport ordinary stopping bus services for journeys wholly within the Greater London area (e.g. 402 Bromley North-Pratts Bottom or 370/373 Romford - Corbetts Tey are OK. The general exceptions are the Green Line and other express type services e.g. Airbus or Oxford Tube services not OK). Also, some non London Transport services are valid for sections outside the usual area as well as the usual part within it... They are: 84 beyond Hadley Highstone through to South Mimms, 301 & 549 Roding Valley to Loughton Traps Hill, 511/512 beyond Lovelace Road to Effingham Road Ewell Road, 420 to Banstead (Victoria), 610 to Cuffley Station.
Also valid on: Services from Inside that go out: Many London Transport Bus Services are valid throughout their entire length even though some or much of this may be outside the Greater London area... These are: 20, 80, 81, 96, 107, 142, 167, 203, 233, 235, 258, 290 (to Staines Sainsburys), 292, 298, 313, 331, 350, 383, 400 (to Ashford Common, Spelthorne), 403, 404, 405, 407, 428, 465 (to Leatherhead), 466, 492, B15, K3, S1 and W10. Thus travel to Potters Bar, Slough, Epping, Redhill and Bluewater Shopping Centre are all possible within the scope of this ticket though these locations are well outside the usual area, however travel to these places is ONLY available on the services listed above, and not ALL services to these locations (even if that service runs there from within the London area!! eg 81 to Slough is OK but not 58 from Uxbridge to Slough even though Uxbridge is within the London Area. Example 2: 96 ok to Bluewater but not 477 from Orpington to Bluewater, even though Orpington is within London area.)
Not Valid on: Off Peak version not valid Monday-Friday before 9.30am, Both types not valid on certain special services and excursions (710, Round London Sightseeing Tour, Airbuses, Green Line etc)
One Day Travelcard (i.e. not for 'ALL ZONES' as above, but only some): Cannot be bought on the bus. Buy on the day from Underground or Railway stations within the zones required. Adult Off Peak: Zones 1 & 2 £4.10 (up 10p), Zones 1 to 4 £4.40 (up 10p),  Zones 2 to 6 £3.50 (no Change). Peak versions: Zones 1 & 2 Adult £5.30, Child £2.60; Zones 1, 2 & 3 Adult £6.20, Child £3.10; Zones 1, 2, 3 & 4 Adult £6.80, Child £3.40; Zones 1, 2, 3, 4 & 5 Adult £8.70, Child £4.30. The only child off peak version is for all zones at £2.
Valid on: As per all zone travelcards within their zones of validity, except that to be valid for travel on inside services that go out, the travelcard must cover a minimum of 2 zones including Zone 4.
Not Valid on: Off Peak not before Monday-Friday before 9.30am, Peak and Off Peak versions not valid on certain special services and excursions (710, Airbuses, Green Line etc). Only travelcards valid for at least zones 4 and 5 may be used on the 726. 
Weekend Travelcard: Zones 1 & 2 £6.10 (up 10p) Adult, Zones 1 to 4 £6.60 (up 20p) Adult, All Zones Adult £7.50 (up 30p), Zones 2 to 6 Adult £5.20 (no change), Child (any combination of zones £3 (no change)
Valid on: Allows travel all day on Saturday and Sunday, or 2 consecutive days over bank holiday weekends. Valid as per equivalent One day version.
Family Travelcard: As per equivalent full version, except that for 1 or 2 adults travelling with between 1 and 4 children this is a cheaper option. All members of the group must hold a Family Travelcard, though the group members do not need to be related. Zones 1 & 2 Adult £2.70 (up 10p), Zones 1 to 4 £2.90 (up 10p), All zones Adult £3.30 (up 10p), Zones 2 to 6 Adult £2.30 (no change), Child (any zone compination) 80p (no change)
Travelcard Seasons: May be bought up to 4 days in advance of commencement from Underground or National rail stations. Available for 7 days, monthly or for any longer period up to one year. Child rate Travelcard seasons are valid for a maximum period of 4 months. Travelcard seasons can start on any day of the week. A valid photocard is required, but there are no time restrictions and it is valid on N-prefixed night services in the zones selected. Example rates: All zones: Adult £36.90 7 days (up 50p),  £141.70 Monthly (up £1.90), £1476 annually (up £20). Child all zones £15.70 7 days (up 30p), £60.30 monthly (up £1.10). 4 zones: Zones 1-4, Adult £28.10 7 days (up 50p), £108 monthly (up £2) , £1124 annually (up £20). Child 4 zones: zones 1-4 £13 7 days (up 20p), £50 monthly (up 80p). 4 zones without Zone 1 (i.e. 2 to 5 or 3 to 6) Adult £20.70 7 days (up 20p), £79.50 monthly (up 70p), £828 annually (up £8). Child 4 zones without zone 1 (i.e. 2 to 5 or 3 to 6) £10.30 7 days (up 10p), £39.60 monthly (up 40p). An annual travelcard season is known as a gold card and offers various other travel discounts when either travelling by train outside of London at offpeak times, or when buying one day travelcards for friends inside London.
All Zone One Day LT card: All day version of travelcard but without most of the National rail element. Cannot be bought on the bus. Buy on the day from Underground stations within Greater London. One day: £7.90 Adult (up 20p), £3.40 Child (up 10p).
Valid on: All London Underground lines except Bakerloo Line north of Kenton. Docklands Light Railway, Croydon Tramlink, all Buses in Greater London which display the 'London Transport Bus Service' sign, including Express 726. National Rail services on the following sections only: Amersham-Marylebone, Finsbury Park - Kings Cross/Moorgate, Kentish Town-Moorgate/Elephant/London Bridge, Richmond - Gunnersbury, Stratford - Liverpool Street, Stratford - Custom House, West Ruislip - South Ruislip and Upminster - Fenchurch Street/Liverpool Street (But not at Forest Gate/Maryland). Also valid on LT N-Prefixed Night buses for journeys which commence anytime before 4.30am on the morning following expiry.
Also valid on: Services from Outside that go in: Most non London transport ordinary stopping bus services for journeys wholly within the Greater London area (the exceptions are the Green Line and other express type services). Also, some non London Transport services are valid for sections outside the usual area as well as the usual part within it... They are: 84 beyond Hadley Highstone through to South Mimms, 301 & 549 Roding Valley to Loughton Traps Hill, 511/512 beyond Lovelace Road to Effingham Road Ewell Road, 420 to Banstead (Victoria)
Also valid on: Services from Inside that go out: Many London Transport Bus Services are valid throughout their entire length even though some or much of this may be outside the Greater London area... These are: 20,80, 81, 96, 107, 142, 167, 203, 233, 235, 258, 290 (to Staines Sainsburys), 292, 298, 313, 331, 383, 400 (to Ashford Common, Spelthorne), 403, 404, 407, 409 (to Caterham Golden Lion), 428, 465 (to Leatherhead), 466, 492, B15, K3, S1 and W10. Thus travel to Potters Bar, Slough, Epping and Bluewater Shopping Centre are possible within the scope of this ticket though these locations are well outside the usual area, however travel to these places is only available on the services listed above, and not ALL services to these locations....
Not Valid on: Certain special services and excursions (710, Airbuses, Green Line etc)
Bus Passes:  As per equivalent LT card, but with no Underground, Tramlink, or Express 726 validity. They are valid all day, but will need to be bought from Underground stations, pass agents or from the limited number of roadside ticket machines. One Day All zones Adult £2 (no change), Child £1 (no change).
Period Bus Passes: Available for 7 days, monthly or for any longer period up to one year. Child rate Period Bus Passes are valid for a maximum period of 4 months. Period Bus Passes can start on any day of the week. There are no time restrictions and it is valid on N-prefixed night services in the zones selected. Example rates: All zones Adult £8.50 7 days,  £32.70 Monthly, £340 annually. Child all zones £4 7 days, £15.40 monthly. 1 zone of 2 or 3 or 4 (bus zone 4 comprises rail zones 4,5 & 6) Adult £7.50 7 days, £28.8 monthly, £300 annually.
One Day Bus & Tram Pass: As per Bus only Pass with added Tramlink. Valid all day, to 4.30am the following morning. One day aLL Zones Adult £2.80, Child £1.20 (no change either adult or child). Like bus pass this ticket is not valid on 726 etc.
Some other tickets are available -  'Youth' LT Card and Bus Passes for 16 and 17 year olds, plus Carnet tickets and Group day tickets on the underground for regular Zone 1 travellers or large groups travelling together. There is also a range of DLR Shuttle and City Flyer tickets for unlimited travel on various sections of the Docklands Light Railway. Ring  London Transport Travel Enquiries on (020) 7222 1234, 24 hours a day. Monthly or annual passes may also be ordered by Credit or Debit card on (0870) 849 9999 daily between 8am and 10pm.